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In this study, we designed novel self-healing hydrogels (CMC/DAQP-HGs) using carboxymethyl chitosan (CMC) and dialdehyde quaternized pullulan (DAQP), aimed at loading tranexamic acid (TA) for rapid hemostasis. Meanwhile, CMC/dialdehyde pullulan (DAP) hydrogels (CMC/DAP-HGs) were prepared for comparison with CMC/DAQP-HGs. Experimental results showed that (1) DAQP, DAP, CMC/DAQP-HGs, and CMC/DAP-HGs were successfully prepared; (2) both types of hydrogels demonstrated excellent swelling (swelling ratio of 12.66-22.18 g/g), water retention (> 24 h), self-healing, and injectable properties, biocompatibility (hemolysis ratio < 2 %, relative cell viability of L929 and HSF > 80 %), and degradability; (3) CMC/DAQP-HGs had superior adhesive, antibacterial, and hemostatic properties compared to CMC/DAP-HGs, with CMC/DAQP-HG1 showing the best performance, including a tissue adhesion strength of 6.54 kPa, ~100 % of inhibition against E. coli and S. aureus, and hemostasis time in the three animal models <312 s; (4) the novel hydrogels effectively encapsulated tranexamic acid (TA) and controlled TA release; and (5) the addition of TA significantly enhanced the hydrogels' hemostatic efficacy, with the hemostasis time values in the TA-loaded CMC/DAQP-HG1 (TA/CMC/DAQP-HG1) group being reduced by >56 % compared to those in the gelatin sponge group, indicating that TA/CMC/DAQP-HG1 had the potential to be an ideal hemostatic dressing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

AMPK is a key regulator of metabolism in eukaryotes across various pathways related to energy regulation. Although extensive investigations of AMPK have been conducted in mammals and some model organisms, research on AMPK in scallops is comparatively limited. In this study, three AMPK family genes (AiAMPKα, AiAMPKβ and AiAMPKγ) in scallop Argopecten irradians irradians were identified through genome scanning. Structure prediction and phylogenetic analyses of AiAMPKs were performed to determine their structural features and evolutionary relationships. Spatiotemporal expression patterns of AiAMPKs at different developmental stages and in healthy adult tissues were analyzed to elucidate the function of AiAMPKs in bay scallops' growth and development. The spatiotemporally specific expression of AiAMPKs implied their important roles in growth and development of bay scallops. Heat stress experiment was performed to determine the regulations of AiAMPKs in four kinds of thermosensitive tissues. Expression profiles revealed distinct molecular mechanisms of AiAMPKs in different tissues in response to heat stress: significant down-regulations in mobile hemocytes, but dominant up-regulations occurring in stationary gills, mantles and hearts. Functional verification including knock-down of AiAMPKα and inhibition of AiAMPK was separately conducted in the thermotolerant tissue heart at the post-transcription and translation levels. The thermotolerant index Arrhenius break temperature (ABT) showed a significant decrease and the rate-amplitude product (RAP) peaked earlier in the individuals after RNAi targeting AiAMPKα, displaying an earlier transition to anaerobic metabolism under heat stress, indicating an impairing ability of aerobic metabolism. After AiAMPK inhibition, widespread down-regulations of genes in key energy metabolism pathways, RNA polymerase II-mediated transcription, and aminoacyl-tRNA synthesis pathways were obviously observed, revealing the post-translational inhibition of AiAMPK hindered cardiac energy metabolism, basal transcription and translation. Overall, our findings provide evidences for exploring the molecular mechanisms of energy regulation in thermotolerant traits in bay scallops under ongoing global warming., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Trimethylamine (TMA), a simple trace biogenic amine resulting from the decomposition of proteins and other macromolecules, is ubiquitous in nature. It is found in the human gut as well as in various terrestrial and marine ecosystems. While the role of TMA in promoting cardiovascular diseases and depolarizing olfactory sensory neurons in humans has only recently been explored, many microbes are well known for their ability to utilize TMA as a carbon, nitrogen, and energy source. Here, we report the first structure of a TMA transporter, TmaT, originally identified from a marine bacterium. TmaT is a member of the betaine-choline-carnitine transporter family, and we show that TmaT is an Na + /TMA symporter, which possessed high specificity and binding affinity toward TMA. Furthermore, the structures of TmaT and two TmaT-TMA complexes were solved by cryo-EM. TmaT forms a homotrimer structure in solution. Each TmaT monomer has 12 transmembrane helices, and the TMA transport channel is formed by a four-helix bundle. TMA can move between different aromatic boxes, which provides the structural basis of TmaT importing TMA. When TMA is bound in location I, residues Trp146, Trp151, Tyr154, and Trp326 form an aromatic box to accommodate TMA. Moreover, Met105 also plays an important role in the binding of TMA. When TMA is transferred to location II, it is bound in the aromatic box formed by Trp325, Trp326, and Trp329. Based on our results, we proposed the TMA transport mechanism by TmaT. This study provides novel insights into TMA transport across biological membranes., Importance: The volatile trimethylamine (TMA) plays an important role in promoting cardiovascular diseases and depolarizing olfactory sensory neurons in humans and serves as a key nutrient source for a variety of ubiquitous marine microbes. While the TMA transporter TmaT has been identified from a marine bacterium, the structure of TmaT and the molecular mechanism involved in TMA transport remain unclear. In this study, we elucidated the high-resolution cryo-EM structures of TmaT and TmaT-TMA complexes and revealed the TMA binding and transport mechanisms by structural and biochemical analyses. The results advance our understanding of the TMA transport processes across biological membranes., Competing Interests: The authors declare no conflict of interest.

Heat shock proteins (Hsps) are highly conserved molecular chaperones with essential roles against biotic and abiotic stressors. A large set of co-chaperons comprising J-domain proteins (DnaJs) regulate the ATPase cycle of Hsp70s with Hsp90s, together constituting a dynamic and functionally versatile network for protein folding/unfolding and regulation. Marine bivalves could accumulate and tolerate paralytic shellfish toxins (PSTs), the well-noted neurotoxins generated during harmful algal blooms. Here, 37 CfDnaJ and 35 PyDnaJ genes were systematically characterized in Zhikong scallop (Chlamys farreri) and Yesso scallop (Patinopecten yessoensis), the important aquaculture bivalve species in China. After exposure to different PST-producing dinoflagellates, Alexandrium minutum and Alexandrium catenella, diverse DnaJ regulations were presented in scallop hepatopancreas, accumulating incoming PSTs, and kidneys, transforming PSTs into higher toxic analogs. CfDnaJs' up-regulation in kidneys was similar with that in hepatopancreas, while their down-regulation was stronger in kidneys than in hepatopancreas, with CFA.38965.19.DNAJC30 being continuously down-regulated in both tissues of the two algae exposure. Moreover, PyDnaJs' up-regulation was only found in kidneys after A. catenella exposure, and PYE.10799.6.DNAJB1 was down-regulated in both tissues through the experiment. Together with the expression trends and correlation of DnaJ-Hsp70-Hsp90 genes, the organ-, toxin-, and species-dependent Hsp70B2 expressions were coordinately co-expressed with diverse DnaJ members, suggesting the functional diversity of scallop DnaJs with conserved Hsp70B2s in response to stress by PST-producing algae. Our results confirmed the regulated coordination of DnaJ-Hsp70B2 co-chaperons in scallops, and provided vital insights into the function and adaptation of scallop Hsps in response to PST stress., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 The Authors. Published by Elsevier Inc. All rights reserved.)

This study utilizes the Analytic Hierarchy Process (AHP) to prioritize climate change mitigation strategies for coastal regions systematically. The AHP, a robust data-driven decision-making framework, was employed to evaluate five strategies: Mangrove Restoration, Zoning and Building Codes, Seawalls, Coral Reef Protection, and Relocation Programs. The analysis revealed that Mangrove Restoration emerged as the most effective strategy, achieving the highest score of 0.65 due to its significant environmental impact and long-term sustainability. Zoning and Building Codes followed closely with a score of 0.58, showcasing their cost-effectiveness and regulatory advantages. While effective in urban areas, Seawalls ranked third with a score of 0.48, indicating limitations in social acceptance. Coral Reef Protection and Relocation Programs scored 0.46 and 0.38, respectively, reflecting their higher costs and resource intensity. The findings underscored the importance of prioritizing strategies that balance ecological health and socio-economic feasibility, offering actionable recommendations for policymakers and stakeholders. This research identifies key challenges such as balancing ecological health, socio-economic feasibility, and resource limitations. Our framework addresses these by integrating multi-criteria evaluation, presenting novel prioritization insights for climate adaptation strategies in coastal regions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Prenylation modifications of natural products play essential roles in chemical diversity and bioactivities, but imidazole modification prenyltransferases are not well investigated. Here, we discover a dimethylallyl tryptophan synthase family prenyltransferase, AuraA, that catalyzes the rare dimethylallylation on the imidazole moiety in the biosynthesis of aurantiamine. Biochemical assays validate that AuraA could accept both cyclo-(L-Val-L-His) and cyclo-(L-Val-DH-His) as substrates, while the prenylation modes are completely different, yielding C2-regular and C5-reverse products, respectively. Cryo-electron microscopy analysis of AuraA and its two ternary complex structures reveal two distinct modes for receptor binding, demonstrating a tolerance for altered orientations of highly similar receptors. The mutation experiments further demonstrate the promiscuity of AuraA towards imidazole-C-dimethylallylation. In this work, we also characterize a case of AuraA mutant-catalyzed dimethylallylation of imidazole moiety, offering available structural insights into the utilization and engineering of dimethylallyl tryptophan synthase family prenyltransferases., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Deep-sea sediments contain a large number of Thaumarchaeota that are phylogenetically distinct from their pelagic counterparts. However, their ecology and evolutionary adaptations are not well understood. Metagenomic analyses were conducted on samples from various depths of a 750-cm sediment core collected from the Mariana Trench Challenger Deep. The abundance of Thaumarchaeota and archaeal amoA generally decreased with depth, except for an unexpected peak midway through the core. The thaumarchaeotal metagenome-assembled genomes were classified into diverse phylogenetic clusters associated with amoA-NP-γ, amoA-NP-θ, and amoA-NP-δ of ammonia-oxidising Thaumarchaeota and non-ammonia-oxidising lineages. The most abundant group was within amoA-NP-γ, which is usually found in coastal and shallow habitats, indicating potential niche expansion from marine shallow to hadal environments. This benthic group showed within-species genomic variations compared to the previously identified Hadal water group, suggesting microdiversification of hadal Thaumarchaeota along with niche separation between benthic and pelagic environments. Evolutionary adaptations associated with the benthic-to-pelagic transition included reduced genome size, loss of motility/cell adhesion, altered energy metabolism, and different mechanisms for substrate acquisition and regulation (e.g., ammonium). These findings offer new insights into the evolution of hadal Thaumarchaeota and demonstrate, for the first time, intraspecies-level genomic variation in Thaumarchaeota related to the benthic-versus-pelagic niche partitioning in the deep ocean., (© 2025 John Wiley & Sons Ltd.)

Considering the limitations of human corneal endothelial cell proliferation as well as the severe shortage of corneal donations, it is imperative to develop improved methods of corneal endothelial cell transplantation. The purpose of this study was to construct a modified corneal endothelial cell transplantation approach using thermosensitive hydrogels combined with induced pluripotent stem cells (iPSCs)-derived human corneal endothelial cells (hCECs). In this study, thermosensitive hydrogels hydroxypropyl chitin/carboxymethyl chitosan (HPCH/CMCS) were fabricated, and their hydrogels properties and biocompatibility were investigated. Our results demonstrated that HPCH/CMCS hydrogels exhibited superior transparency, appropriate mechanical properties and favorable biocompatibility. A two-step induction method of small molecule compounds was employed, by which iPSCs were differentiated into hCECs via neural crest cells (NCCs). Additionally, a rabbit corneal endothelial dysfunction model was established in vivo, aiming to evaluate the safety and effectiveness of the combined method. Slit lamp microscope results indicated that significant transparency improvement could be noted in HPCH/CMCS/hCECs group (P = 0.006), whereas the corneal transparency was not homogeneous in different areas. Moreover, histological examinations and immunofluorescence analysis revealed that HPCH/CMCS/hCECs group showed a higher density of corneal endothelial cells and positive expressions of related markers. This study may provide ideas and experimental basis for the combined application of hydrogels and iPSC-derived corneal endothelial cells for corneal endothelial dysfunction. STATEMENT OF SIGNIFICANCE: Corneal transplantation is the most effective treatment for corneal endothelial dysfunction, which is challenged by issues such as corneal donor shortages and immune rejection. In this study, we proposed a combined transplantation method of cells and hydrogels for corneal endothelial dysfunction. We modified the protocols to obtain corneal endothelial cells from iPSCs by a two-step induction method. Besides, thermosensitive hydrogels with satisfactory biocompatibility and degradability were fabricated as fixation and support carriers of iPSC-derived corneal endothelial cells for in vivo transplantation. Experimental results demonstrated that this method could locally repair corneal endothelial dysfunction in rabbits, with the repaired corneas expressing relevant markers. This study presented a preliminary attempt to combine hydrogels and cells for corneal endothelial dysfunction., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Across large oceanic spatial scales, the mechanisms governing microbial community composition remain poorly understood, particularly regarding the influence of biotic factors. In this study, samples were collected over a 3772.55-km transect in the Western Pacific surface waters, with 16S and 18S ribosomal RNA gene sequencing employed to elucidate the assembly processes and drivers of microbial communities. Both eukaryotic (EM) and prokaryotic microbial (PM) communities exhibited a significant distance-decay relationship throughout the survey, although their assembly mechanisms differed. Biotic factors played a pivotal role in shaping the biogeographical patterns of both EM and PM communities, indicating that cross-domain microbial interactions significantly affect each other's distribution. Furthermore, the stability of the co-occurrence network was more strongly influenced by cross-domain microbial relationships than by keystone taxa. These findings advance our understanding of the mechanisms and biogeographical patterns sustaining microbial diversity across large oceanic spatial scales., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Benthic diatoms serve as exemplary indicators for the assessment of ecological conditions in freshwater ecosystems. However, an approach to assessing and managing transitional water zones by benthic diatoms is relatively less. This study entailed a detailed analysis and comparison of the seasonal dynamics in species- and guild-based benthic diatom communities and their driving factors in a small-scale transitional water zone of the Yellow River Delta. Our findings revealed substantial seasonal variations in the composition and abundance of dominant species, as well as in the α and β diversity of the species-based community. Temperature emerged as the predominant environmental factor driving significant seasonal variations in the species-based community. However, no significant seasonal changes were observed in the composition and relative abundance of dominant guilds, as well as in the α, β, and functional diversity of the guild-based community. Redundancy analysis and Mantel tests demonstrated the guild-based community exhibited a stronger correlation with environmental factors compared to the species-based community. The guild-based community exhibited resilience to the influence of seasonal temperature fluctuations and exhibited a strong correlation with phosphate concentration variations. Our findings suggest that the guild-based community is a feasible approach to assessing ecological status across various seasons in the transitional water zone of the Yellow River Delta., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Coxiella burnetii (C. burnetii)is a significant microbe linked to the zoonotic disease Q fever, known for its atypical clinical manifestations and sporadic cases. It can cause lumbar infections. In this report, we present a 66-year-old male sheep farmer who experienced low back pain for five months, with worsening numbness in both lower limbs over two months. Several standard diagnostic tests were negative. Metagenomic next-generation sequencing (mNGS) was performed on lumbar spine tissue obtained via biopsy, identifying C. burnetii infection. After surgical excision of the lesion, the patient received a combination of levofloxacin, doxycycline, rifampicin, and supportive medications. Postoperatively, the patient's condition stabilized, showing a significant reduction in low back pain. This case highlights mNGS as a valuable tool for diagnosing rare infections, especially in patients with a history of animal exposure. It underscores the importance of considering zoonotic infections and the need for combined antibiotic and surgical management in suspected cases., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024. Published by Elsevier Inc.)

Microalgae-based approaches serve as promising methods for the remediation of pharmaceutical contaminants (PCs) compared to conventional wastewater treatment processes. However, how to decrease hydraulic retention times of the microalgal system currently has been one of the main bottlenecks. This study constructed an unexpected synergistic extra-chemical/intra-biological degradation system by adding 5.95 mM bicarbonate to the microalgal system, which achieved complete removal (100%) of a representative PC, doxylamine (DOX) in 96 h, compared to that 192 h in the control. Removal capacities and mass balance analyses demonstrated that biodegradation rate per unit microalgal density was significantly increased by 207%. Further analyses using transcriptomic, enzymatic inhibiting tests, and high-resolution mass spectrometry revealed that after addition of bicarbonate for metabolism of DOX, a hydrolase (CYP97C1) and a primary amine oxidase (TynA) can transform DOX into doxylamine N-oxide and an intermediate (C 15 H 17 NO 2 ) with a m/z of 244.1335. Meanwhile, bicarbonate reacted with microalgae-excreted hydrogen peroxide to form more oxidative radicals such as superoxide and hydroxyl radicals extracellularly, which promised the extracellular degradation of DOX according to the oxidative radical inhibiting tests. Further investigation showed addiing bicarbonate to the microalgal system improved the removal rate of 17 PCs by up to 500.8%. Therefore, this study not only developed an approach to enhance treatment efficiencies of diverse PCs by microalgae within a shorter time, but also carried unique mechanistic insights into the underlying principles., Competing Interests: Declaration of competing interest The authors declare no conflicts of interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Okadaic acid (OA), a predominant toxic entity in Diarrhetic Shellfish Poisoning (DSP), carries substantial significance for both marine ecosystems and human well-being. The nascent organic photoelectrochemical transistor (OPECT) biosensor has emerged as a promising biometric methodology, poised to offer a fresh realm for the detection of marine biotoxins. In this work, a biosensor utilizing signal amplification based on Cd 0.5 Zn 0.5 S/ZnIn 2 S 4 quantum dots (CZS/ZIS QDs) in OPECT was proposed for OA detection, where ZIS QDs were labeled on aptamer and a substantial quantity of QDs were generated via cyclic shearing facilitated through target-induced Exo I enzyme. Owing to the sensitizing influence of ZIS QDs on CZS, the photoelectric conversion efficiency was augmented, culminating in a notable anodic photocurrent upon exposure to light, thereby inducing a transformation in the channel state of the polymer poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) and consequently producing a remarkable modification in the channel current. The detection limit of the biosensor as low as 12.5 pM and a superior stability and specificity was confirmed, which also showed commendable outcomes in actual samples testing. Consequently, this study not only introduces a novel pathway for swift OA detection, but unveils a novel perspective for future expedited and convenient on-site detection of marine biotoxins., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The razor clam Sinonovacula constricta , a significant marine bivalve species, inhabits estuaries and encounters salinity stress. Despite its commercial importance, there is limited understanding of its adaptive mechanisms to high salinity. Aldehyde dehydrogenases (ALDHs), which belong to the NAD(P) + -dependent superfamily, play a crucial role in stress resilience by participating in catabolic and anabolic pathways, such as carnitine synthesis, glycolysis, and amino acid metabolism. This study presents the first comprehensive analysis of the ALDH family in S. constricta under acute high salt stress conditions and identifies 16 ScALDH genes across 10 subfamilies. These genes are located on eight chromosomes, with tandem duplications observed on chromosome 10; they encode mostly acidic and hydrophilic proteins. Among them, ScALDH18A1 contains a conserved P5CS domain that is implicated in proline synthesis and osmotic regulation. The expression of 14 ScALDH members were significantly altered under acute salt stress conditions, with ScALDH8 and ScALDH18A1 showing increased expression levels, suggesting their involvement in osmotic pressure regulation. This research provides insights into the characteristics, evolution, and response to salinity stress of the ScALDH gene family while shedding light on ALDH function in bivalves, as well as serving as a foundation for further studies on osmotic stress regulation.

The Sox family genes, as a group of transcription factors, are widely expressed in vertebrates and play a critical role in reproduction and development. The present study reported that 26 sox genes were identified from the genome and transcriptome of P. leopardus. The phylogenetic tree construction, chromosome localization, and gene structure analysis were executed to verify the evolutionary relationships, gene duplication, and deletion variations of P. leopardus sox genes in evolution. The sequence alignment revealed the HMG-box domain was highly conserved throughout the Sox gene family. The expression profile showed expression levels of sox genes showed tissue specificity. The dimorphic expression pattern of most sox genes in intersex and adult gonads was also observed, suggesting an important role of sox genes for sex differentiation in P. leopardus. Notably, sox32 was specifically highly expressed in gonadal tissues and might play a novel role within the gonads. The fluorescent in situ hybridization (FISH) showed sox32 mRNA was detected in germ stem cells and oocytes of different stages, and lowly expressed in sertoli cells. In testis, sox32 was not detected in male germ cells. Our results provided new insights into the sox32 that might be involved in gonadal development and differentiation in P. leopardus. To sum up, this study comprehensively analyzed the Sox gene family of P. leopardus and provided new insights into the function of sox genes, which could potentially revolutionize our understanding of the mechanisms of sex determination, sex differentiation, and reproductive development in fish., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Triploids are widely used to rapidly achieve genetic improvements of organisms due to their fast growth and enhanced environmental adaptability. Artificially induced triploids are generally considered to be infertile owing to the obvious inhibition of gonadal development. Recently, some fertile individuals with reduced advantages have been found in triploid bivalves, which is a notable deviation from the original intention of artificially inducing triploids. This study utilized dwarf surf clams (Mulinia lateralis), a promising model organism of bivalves, to develop a model for exploring the potential mechanism of triploid reproduction. The results showed that the optimal induction condition for triploid M. lateralis, determined by orthogonal experiments, was 0.5 mg/L cytochalasin B (CB) to inhibit PB2 for 20 min, resulting in a triploidy rate of 95.57% and a hatching rate of 60.25%. By tracking the development of M. lateralis, we found that the induced triploids could develop normally to maturity and exhibited significant growth and survival advantages post-metamorphosis. Although the triploidy rate exhibited a slight decline overtime, it remained high, with a ratio of 90.63% at 120 dpf. Histological observation confirmed that the gonadal development pattern of triploid M. laterali was similar to that of diploids, but it also showed characteristics such as developmental retardation, few mature gametes, and gamete gigantism. The dynamic expression of genes related to gonadal development provided further molecular evidence for this phenomenon. Additionally, 82.6% of triploid M. laterali exhibited normal spawning behavior, produced fewer but larger viable gametes, and could generate offspring with full developmental potential. Flow cytometry analysis revealed that sperm of triploid M. laterali was aneuploid, with a DNA content of about 1.5 times that of diploid sperm, and the ploidy levels of mating offspring were 2N (DD, diploid female × diploid male), 2.5N (DT, diploid female × triploid male), 2.5N (TD, triploid female × diploid male), and 3N (TT, triploid female × triploid male), respectively. Overall, the artificially induced triploid M. laterali has been confirmed to be bisexually fertile, which will provide a unique model for exploring the underlying mechanisms of advantageous trait formation and fertility regulation in triploids, and offer a valuable platform for the study of ploidy control and polyploidization in bivalves. Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary. Yes, i have checked and it is OK., Competing Interests: Declarations. Competing Interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Emergency bleeding presents significant challenges such as high blood flow and rapid hemorrhaging. However, many existing hemostatic bandages face limitations, including the uncontrolled release of hemostatic agents, insufficient mechanical strength, poor adhesion, and complex manufacturing processes. To address these limitations, we developed a multifunctional hydrogel bandage for emergency hemostasis using a one-pot synthesis method. The hydrogel was composed of kaolin, N-hydroxysuccinimide-grafted oxidized microcrystalline cellulose (OMCC-NHS), and polyacrylic acid (PAA). Featuring a multi-crosslinked network, it exhibited favorable elasticity (∼942 %), tensile strength (∼220 kPa), fatigue resistance, and robust tissue adhesion (∼55 kPa)-3.9 times stronger than commercial wound-closure strips, and it maintained adhesion even underwater. In addition to its mechanical properties, the hydrogel also exhibited satisfactory antibacterial activity, cytocompatibility, and histocompatibility. In vivo evaluations revealed an impressive hemostatic performance in rat models of liver bleeding, femoral artery bleeding, and tail amputation. Specifically, in the liver bleeding model, the hydrogel reduced blood loss to only 0.1 g, which is just 32 % of the blood loss seen with medical gauze. Notably, in New Zealand rabbit models with cardiac punctures and liver injuries, the hydrogel achieved rapid hemostasis and stopped the bleeding within seconds. The effective hemostatic ability of this hydrogel is primarily due to its ability to facilitate multistep hemostasis, which includes sealing the wound, rapidly absorbing blood, promoting RBC and platelets adhesion, and activating the intrinsic coagulation cascade. Therefore, this study provides a promising approach for developing gel-based hemostatic bandages, specifically tailored for emergency compressible bleeding scenarios., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Lacking of suitable fish muscle stem cell line has greatly hindered the fabrication of cell-cultured fish meat. Here, we established and characterized a spontaneously immortalized marine fish muscle stem cell line (EfMS) from brown-marbled grouper (Epinephelus fuscoguttatus), which could actively proliferate with good genetic stability and well maintain the stemness of myogenesis potential for over 50 passages. Taurine was found to be able to serve as a substitute of fish muscle extract in maintaining stemness. The EfMS cells could be efficiently induced to myogenic differentiation or adipogenic trans-differentiation in both 2D and 3D culture systems. Using edible 3D microcarriers, we produced 0.65 g fat-free and 1.47 g fat-containing cell-cultured fish meat in 8 days. The scaffold-free cell-cultured fish meat exhibited a much higher content of flavory amino acids than natural fish. Together, EfMS cell line can serve as an ideal seed cell line for the production of cell-cultured fish meat., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

We examined the bioavailability of synthetic organic Cu complexes (Cu-L) and inorganic Cu species (Cu') to Thalassiosira oceanica growing under Cu-limiting and Cu-inhibiting conditions. Copper bioavailability depended on the phytoplankton Cu nutritional state and whether Cu' diffusion to the cell surface was sufficient to meet the cellular demands for growth. Under Cu-limiting conditions when [Cu'] was less than the diffusion concentration threshold (DCT: 10 -14.13 M), growth rate was a hyperbolic function of [Cu-L]. Increasing [Cu'] above the DCT caused growth rate to increase proportionally, but growth rate also increased with increasing [Cu-L] so that both Cu' and Cu-L were bioavailable. Short-term photosynthesis assays conducted under Cu-limiting conditions showed a similar response to Cu speciation. In contrast, the growth rate of Cu-inhibited cells at high [Cu'] varied inversely with [Cu 2+ ] and was independent of [Cu-L], as previously reported. The change in Cu-L bioavailability correlated with expression levels of genes encoding the reduction-dependent, high-affinity Cu uptake pathway, which was regulated by [Cu']. Our analysis shows that at [Cu'] typical of the open sea, T. oceanica -like phytoplankton are diffusion limited and must rely on Cu-organic complexes to fulfill their Cu requirements for growth.

Pseudoalteromonas are widely distributed in marine extreme habitats and exhibit diverse extracellular protease activity, which is essential for marine biogeochemical cycles. However, our understanding of viruses that infect Pseudoalteromonas remains limited. This study isolated a virus infecting Pseudoalteromonas nigrifaciens from Xiaogang in Qingdao, China. vB&#95;PunP&#95;Y3 comprises a linear, double-strand DNA genome with a length of 48,854 bp, encoding 52 putative open reading frames. Transmission electron microscopy demonstrates the short-tailed morphology of vB&#95;PunP&#95;Y3. Phylogenetic and genome-content-based analysis indicate that vB&#95;PunP&#95;Y3 represents a novel virus family named as Poorviridae , along with three high-quality uncultivated viral genomes. Biogeographical analyses show that Poorviridae is distributed across five viral ecological zones, and is predominantly detected in the Antarctic, Arctic, and bathypelagic zones. Comparative genomics analyses identified three of the seven hallmark proteins of N4-like viruses (DNA polymerase, major capsid protein, and virion-encapsulated RNA polymerase) from vB&#95;PunP&#95;Y3, combing with the protein tertiary structures of the major capsid protein, suggesting that vB&#95;PunP&#95;Y3 might evolve from the N4-like viruses., Importance: vB&#95;PunP&#95;Y3 is a unique strain containing three of the seven hallmark proteins of N4-like viruses, but is grouped into a novel family-level viral cluster with three uncultured viruses from metagenomics, named Poorviridae . This study enhanced the understanding about the genetic diversity, evolution, and distribution of Pseudoalteromonas viruses and provided insights into the novel evolution mechanism of marine viruses., Competing Interests: The authors declare no conflict of interest.

Carboxysomes are anabolic bacterial microcompartments that play an essential role in CO2 fixation in cyanobacteria. This self-assembling proteinaceous organelle uses a polyhedral shell constructed by hundreds of shell protein paralogs to encapsulate the key CO2-fixing enzymes Rubisco and carbonic anhydrase. Deciphering the precise arrangement and structural organization of Rubisco enzymes within carboxysomes is crucial for understanding carboxysome formation and overall functionality. Here, we employed cryo-electron tomography and subtomogram averaging to delineate the three-dimensional packaging of Rubiscos within β-carboxysomes in the freshwater cyanobacterium Synechococcus elongatus PCC7942 grown under low light. Our results revealed that Rubiscos are arranged in multiple concentric layers parallel to the shell within the β-carboxysome lumen. We also detected Rubisco binding with the scaffolding protein CcmM in β-carboxysomes, which is instrumental for Rubisco encapsulation and β-carboxysome assembly. Using Quantification conCATamer (QconCAT)-based quantitative mass spectrometry, we determined the absolute stoichiometric composition of the entire β-carboxysome. This study provides insights into the assembly principles and structural variation of β-carboxysomes, which will aid in the rational design and repurposing of carboxysome nanostructures for diverse bioengineering applications., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society of Plant Biologists.)

Bisphenol S (BPS) is commonly used for the industrial production of thermal paper, polycarbonate plastics, epoxy resins and other materials. Studies have reported that BPS can lead to triglyceride (TAG) or/and cholesterol (CHO) accumulation in the liver in zebrafish and mice, but the reasons for the different types of lipids that accumulate in the liver following BPS exposure are unclear. Here, the influences of lower-dose (10 mg/kg body weight/day) and high-dose (50 mg/kg body weight/day) BPS exposure to male SD rats on the accumulation of different lipids in the liver were explored. The results indicated that BPS treatment increased the levels of acetyl-CoA and glycogen in the liver. A lower dose of BPS upregulated the mRNA and protein expression levels of sterol regulatory element-binding protein 1 (srebp1), which is involved in the de novo synthesis of TAG in the liver, thus promoting the synthesis of glycerides (diacetylglyceride and TAG). However, a higher dose of BPS induced CHO accumulation, but inhibited the mRNA expression of genes (i.e., srebp2, hmgcr and hmgcs) involved in the de novo synthesis of CHO in the liver. Excessive accumulation of glycerides and CHO led to destruction of the physiological structure of rat liver, causing disorders in liver function. Our data provide new insight into the different mechanisms by which glyceride and CHO accumulate in the liver after BPS exposure., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

How cells regulate the size of their organelles remains a fundamental question in cell biology. Cilia, with their simple structure and surface localization, provide an ideal model for investigating organelle size control. However, most studies on cilia length regulation are primarily performed on several single-celled organisms. In contrast, the mechanism of length regulation in cilia across diverse cell types within multicellular organisms remains a mystery. Similar to humans, zebrafish contain diverse types of cilia with variable lengths. Taking advantage of the transparency of zebrafish embryos, we conducted a comprehensive investigation into intraflagellar transport (IFT), an essential process for ciliogenesis. By generating a transgenic line carrying Ift88-GFP transgene, we observed IFT in multiple types of cilia with varying lengths. Remarkably, cilia exhibited variable IFT speeds in different cell types, with longer cilia exhibiting faster IFT speeds. This increased IFT speed in longer cilia is likely not due to changes in common factors that regulate IFT, such as motor selection, BBSome proteins, or tubulin modification. Interestingly, longer cilia in the ear cristae tend to form larger IFT compared to shorter spinal cord cilia. Reducing the size of IFT particles by knocking down Ift88 slowed IFT speed and resulted in the formation of shorter cilia. Our study proposes an intriguing model of cilia length regulation via controlling IFT speed through the modulation of the size of the IFT complex. This discovery may provide further insights into our understanding of how organelle size is regulated in higher vertebrates., Competing Interests: YS, ZC, MJ, HX, CZ No competing interests declared, (© 2024, Sun, Chen et al.)

Coastal bays link terrestrial and oceanic carbon reservoirs and play important roles in marine carbon cycles. Particulate organic carbon (POC) produced by phytoplankton is a major autochthonous carbon source in coastal bays. Previous studies on the fate of POC produced by phytoplankton mainly focused on the relationship between phytoplankton and zooplankton in classic food webs, while our knowledge on the roles of bacterioplankton is still limited, particularly in bays under highly intensive aquaculture activities. Here, we investigated bacterial community structure, and the influence of environmental factors and phytoplankton biomass and community structure based on samples collected in August 2022 from Sanggou Bay, a typical aquaculture bay in northern China. Environmental conditions, phytoplankton and bacterial community structure differed significantly between different aquaculture areas, showing higher relative abundance of Synechococcus sp. in the mixing area of shellfish and kelp culture (Area II) than the shellfish culture area (Area I). In contrast, Marivita cryptomonadis was more abundant in Area I, associated with elevated dissolved inorganic nitrogen (DIN), POC, POC/PN (the molar ratio of POC to particulate nitrogen) and sterol-derived total phytoplankton biomass. The strong correlation between total phytoplankton biomass and particle-associated bacteria indicated the important role of this bacterial fraction in processing organic compounds produced by phytoplankton. Significant correlations between bacterial community composition and POC/PN suggested more organic carbon potentially entering detrital biomass pools in Area I compared to Area II. Our results suggest that spatial distribution patterns of bacterial community structure were regulated by multiple abiotic and biotic factors and had a profound impact on the fate of organic carbon under highly intensive aquaculture activities in Sanggou Bay., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The axolotl, a legendary creature with the potential to regenerate complex body parts, is positioned as a powerful model organism due to its extraordinary regenerative capabilities. Axolotl can undergo successful regeneration of multiple structures, providing us with the opportunity to understand the factors that exhibit altered activity between regenerative and non-regenerative animals. This comprehensive review will explore the mysteries of axolotl regeneration, from the initial cellular triggers to the intricate signaling cascades that guide this complex process. We will delve deeply into the multifaceted interplay of genes and factors, highlighting the key role of signaling pathways and the influence of epigenetic modifications (such as DNA methylation, histone modification, and miRNA regulation) during regeneration. Furthermore, we will discuss how axolotls defy the odds by showing remarkable resistance to cancer, offering insights into potential therapeutic strategies. However, that is not the end; we will also highlight how age might affect the regenerative power of this creature. We hope this review will help navigate the awe-inspiring realm of axolotl regeneration, advance our understanding of regenerative biology, and chart pathways for future investigations aimed at uncovering new therapeutic approaches.

Haptophyta represents a major taxonomic group, with plastids derived from the primary plastids of red algae. Here, we elucidated the cryoelectron microscopy structure of the photosystem I-light-harvesting complex I (PSI-LHCI) supercomplex from the haptophyte Isochrysis galbana . The PSI core comprises 12 subunits, which have evolved differently from red algae and cryptophytes by losing the PsaO subunit while incorporating the PsaK subunit, which is absent in diatoms and dinoflagellates. The PSI core is encircled by 22 fucoxanthin-chlorophyll a / c -binding light-harvesting antenna proteins (iFCPIs) that form a trilayered antenna arrangement. Moreover, a pigment-binding subunit, L iFP , which has not been identified in any other previously characterized PSI-LHCI supercomplexes, was determined in I. galbana PSI-iFCPI, presumably facilitating the interactions and energy transfer between peripheral iFCPIs and the PSI core. Calculation of excitation energy transfer rates by computational simulations revealed that the intricate pigment network formed within PSI-iFCPI ensures efficient transfer of excitation energy. Overall, our study provides a solid structural foundation for understanding the light-harvesting and energy transfer mechanisms in haptophyte PSI-iFCPI and provides insights into the evolution and structural variations of red-lineage PSI-LHCIs., Competing Interests: Competing interests statement:The authors declare no competing interest.

Brown algae, constituting the second largest group of marine macroalgae, fix significant amounts of inorganic carbon into alginate, the most abundant polysaccharide found in their cell walls. Alginate serves as an important macromolecular carbon source for marine bacteria. The catabolism of alginate by bacteria is an important step in the marine carbon cycle, and this area of research has attracted growing interests over the past decade. Here, we provide an overview of the recent advances in our understanding of marine bacterial alginate catabolic systems, both in individual organisms and within bacterial consortia, discuss the possibility of additional alginate metabolic pathways in light of the present findings, and highlight the future research foci., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Microbial communities in coastal seas experience strong environmental disturbances, yet their response patterns, especially regarding differently abundant subcommunities, remain poorly understood. Here, through 16S rRNA gene amplicon sequencing, we investigated the diversity, time-decay pattern, and assembly process of abundant, conditionally rare taxa (CRT) and rare microbial subcommunities in temperate coastal waters over 60 consecutive weeks. The abundant (50.9%) and CRT (46.1%) communities each comprised approximately half of the planktonic community, while the CRT and rare communities contributed to the extremely high species diversity. Distinct temporal heterogeneity was observed among the three fractions and was associated with taxonomic level. The abundant subcommunity exhibited time-decay patterns at all taxonomic levels, while for CRT, the pattern was found only at finer levels. In contrast, variations of the rare community loosely followed a temporal rhythm and were largely confined within a specific taxonomic range, likely raised from turnovers among closely related taxa. Determinism dominated the community assembly of the abundant fraction, while the rare one was more controlled by stochasticity that may be related to pulse terrigenous inputs and anthropogenic disturbances. The rare subcommunity with narrow niche widths likely represented a stable repository to offer episodic specialists, while the abundant taxa that exhibited broader niche widths were considered the generalists in fluctuating environments. Our study revealed the distinct strategies that abundant and rare communities adopt to maintain community stability in temporal dynamics of prokaryotic plankton in the coastal seawater., Importance: The relative importance of rare and abundant taxa in microbial temporal patterns remains debated. Here, we identified taxonomically associated distinct diversity modes of abundant and rare subcommunities from a year-round time-series study in dynamic coastal seawater. We highlighted the significance of the rare subcommunity in maintaining community stability by serving as a repository to offer specialists driven by stochastic processes over time. The abundant subcommunity, by contrast, contributed mainly to temporal rhythmic variations. This study expands the current understanding of the temporal dynamics and stability of coastal microbial communities by revealing distinct variation patterns of subcommunities with different abundances.

Residual concentrations of antibiotics in water can reach ng mL -1 - µg mL -1 levels, which pose high risks to crops during irrigation; however, the interactions between rice and antibiotics, as well as the defense mechanisms of rice at their early growth phase remain unclear. In this study, we investigated the uptake dynamics of a ubiquitously found antibiotic, ciprofloxacin (CIP) at 0.1, 1, 6.5, and 20 µg mL -1 in rice seedlings. We found gradually bioaccumulated CIP induced significant physiological changes including inhibited growth of roots and leaves of rice seedlings, and decreased pigment contents, which can be caused by disrupted homeostasis of reactive oxygen species. Integrating roots transcriptomics, metabolomics, and validation experiments, we found that rice seedlings synthesized more gibberellins to trigger the expression of transcription factors such as group VII ethylene response factors, which induced metabolic reprogramming to yield more fatty acids derivates. These compounds including eicosanoids, isoprenoids, and fatty acids and conjugates can act as signaling molecules, as well as antioxidants and energy sources to achieve rice recovery. This conclusion is supported by the evidence showing that adding gibberellins in rice seedlings culture decreased the accumulated CIP and improved rice growth; whilst, disrupting gibberellin signaling pathway using paclobutrazol as an inhibitor increased uptaken CIP in both roots and leaves with augmenting the antibiotic stress on rice. This study has demonstrated a gibberellin-based defense mechanism in rice for defense of CIP stress, which might have significant environmental applications since we can add minor gibberellins to reduce bioaccumulated CIP with simultaneously promoting rice growth at their early phases., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Synthetic photobiocatalysts are promising catalysts for valuable chemical transformations by harnessing solar energy inspired by natural photosynthesis. However, the synergistic integration of all of the components for efficient light harvesting, cascade electron transfer, and efficient biocatalytic reactions presents a formidable challenge. In particular, replicating intricate multiscale hierarchical assembly and functional segregation involved in natural photosystems, such as photosystems I and II, remains particularly demanding within artificial structures. Here, we report the bottom-up construction of a visible-light-driven chemical-biological hybrid nanoreactor with augmented photocatalytic efficiency by anchoring an α-carboxysome shell encasing [FeFe]-hydrogenases (H-S) on the surface of a hydrogen-bonded organic molecular crystal, a microporous α-polymorph of 1,3,6,8-tetra(4'-carboxyphenyl)pyrene (TBAP-α). The self-association of this chemical-biological hybrid system is facilitated by hydrogen bonds, as revealed by molecular dynamics simulations. Within this hybrid photobiocatalyst, TBAP-α functions as an antenna for visible-light absorption and exciton generation, supplying electrons for sacrificial hydrogen production by H-S in aqueous solutions. This coordination allows the hybrid nanoreactor, H-S|TBAP-α, to execute hydrogen evolution exclusively driven by light irradiation with a rate comparable to that of photocatalyst-loaded precious cocatalyst. The established approach to constructing new light-driven biocatalysts combines the synergistic power of biological nanotechnology with the multilength-scale structure and functional control offered by supramolecular organic semiconductors. It opens up innovative opportunities for the fabrication of biomimetic nanoreactors for sustainable fuel production and enzymatic reactions., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Rubisco (ribulose 1,5-bisphosphate carboxylase/oxygenase) is the central enzyme for converting atmospheric CO 2 into organic molecules, playing a crucial role in the global carbon cycle. In cyanobacteria and some chemoautotrophs, Rubisco complexes, along with carbonic anhydrase, are enclosed within specific proteinaceous microcompartments, known as carboxysomes. The polyhedral carboxysome shell ensures a dense packaging of Rubisco and creates a high-CO 2 internal environment to facilitate the fixation of CO 2 . Rubisco and carboxysomes have been popular targets for bioengineering, with the intent of enhancing plant photosynthesis, crop yields, and biofuel production. However, efficient generation of Form 1B Rubisco and cyanobacterial β-carboxysomes in heterologous systems remains challenging. Here, we developed genetic systems to efficiently engineer functional cyanobacterial Form 1B Rubisco in E. coli, by incorporating Rubisco assembly factor Raf1 and modulating the RbcL/S stoichiometry. We further accomplished effective reconstitution of catalytically active β-carboxysomes in E. coli with cognate Form 1B Rubisco by fine-tuning the expression levels of individual β-carboxysome components. In addition, we investigated the encapsulation mechanism of Rubisco into carboxysomes via constructing hybrid carboxysomes; this was achieved by creating a chimeric encapsulation peptide incorporating SSLDs that permits the encapsulation of Form 1B Rubisco into α-carboxysome shells. Our study provides insights into the assembly mechanisms of plant-like Form 1B Rubisco and its encapsulation principles in both β-carboxysomes and hybrid carboxysomes, and highlights the inherent modularity of carboxysome structures. The findings lay the framework for rational design and repurposing of CO 2 -fixing modules in bioengineering applications, e.g. crop engineering, biocatalyst production, and molecule delivery., (Copyright © 2024. Published by Elsevier Inc.)

The contamination of Campylobacter in shellfish poses a health risk for its pathogenicity associated with campylobacteriosis. However, an efficient method to detect this risk is unavailable. Herein, we introduce a portable colorimetric biosensing platform that comprises three modules: an enrichment module 1, a binding and transduction module 2, and a smartphone-based module 3. Module 1 is an aptamer-modified 96-well plate for the specific capture of Campylobacter in a simple and high-throughput manner. Module 2 features a bifunctional biopolymer of L-glutamic acid γ-hydroxamate-alginate-Fe 3+ coordinating fusarinine C, which can bind the captured Campylobacter cells and transduce them into amplified color signals upon reaction with Fe 3+ -violurate complexes. Module 1 achieves a capture efficiency of 97.24 %, and the subsequent addition of module 2 renders colorimetric indication of Campylobacter ranging from 10 1 to 10 6 CFU/mL, achieving an actual limit of detection of 8 CFU/mL validated by Campylobacter single-cells. Moreover, the generated colors can be recognized and converted into cell densities by module 3 with ultrasensitivity. Notably, this biosensor-smartphone platform accomplishe reliable high-throughput colorimetric detection of Campylobacter in real samples with an accuracy of 80 %. This work showcases a proof of principle for efficient on-site detection of Campylobacter contamination regarding shellfish farming., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

UV-B radiation acts as an important environmental factor for aging micro-/nanoplastics (MNPs) in the marine environments, while the effect of aged MNPs on plankton is lacking specific research. Referencing to the UV-B radiation intensity in natural environments (2.29 W·m -2 ), we chose the floating polystyrene (PS) MNPs (50 nm, 1 µm) as the research target in this study. The results indicated that UV-B radiation aging for 30 days led to a rougher surface, increased S BET , increased hydrophobicity, and decreased negative charges of PS MNPs. Correspondingly, aged MNPs increased their adsorption abilities for 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), especially for the initial stage. After UV-B radiation aging processes, the individual toxicities of the two sized MNPs on Thalassiosira pseudonana and Brachionus plicatilis both increased, while their joint toxicities with BDE-47 decreased on T. pseudonana but increased on B. plicatilis. The changes in toxicity were more pronounced in 1 µm PS MNPs under air-aged conditions. This study provided the data basis for evaluating the changes of MNPs environmental behaviors under UV-B radiation in the marine environments, with important ecological significance., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Xylose from lignocellulose is one of the most abundant and important renewable and green raw materials. It is very important how to efficiently transform xylose into useful bioproducts such as fumaric acid and so on., Results: In this study, it was found that the GC1 strain (∆gox, in which the GOX gene encoding glucose oxidase which could transform glucose into gluconic acid was removed) of A. pullulans var. aubasidani DH177 had the high ability to utilize xylose and corncob-derived xylose with CO 2 fixation derived from CaCO 3 to produce calcium fumarate. Overexpression of the XI gene encoding xylose isomerase, the XK gene encoding xylose kinase and the TKL gene coding for transketolase made the strain TKL-4 produce 73.1 g/L of calcium fumarate from xylose. At the same time, the transcriptional levels of the key ASS gene coding for argininosuccinate synthase and the ASL gene coding for argininosuccinate lyase in the ornithine-urea cycle (OUC) were also obviously enhanced. The results also demonstrated that the TKL-4 strain could produce more calcium fumarate from xylose and corncob-derived xylose than from glucose. During 10-liter fermentation, the TKL-4 strain could produce 88.5 g/L of calcium fumarate from xylose, the productivity was 0.52 g/h/L. Meanwhile, it could yield 85.6 g/L of calcium fumarate from corncob-derived xylose and the productivity was 0.51 g/h/L. During the same fermentation, the TKL-4 strain could transform the mixture containing 75.0 g/L glucose and 45.0 g/L xylose to produce 78.7 ± 1.1 g/L calcium fumarate., Conclusions: This indicated that the TKL-4 strain constructed in this study indeed could actively transform xylose and corncob-derived xylose into calcium fumarate through the green ways., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: All the authors have read and checked the revised manuscript and agree that the manuscript is submitted to Microbial Cell Factories and the corresponding authors are Dr. Bo Jiang and Dr and Professor Zhen-Ming Chi. Competing interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024. The Author(s).)

The recently proposed partial denitrification (PD), terminating nitrate reduction to nitrite, has been regarded as a promising alternative to nitrite supplying for anammox bacteria. The most important aspect of the PD process for engineering application is the stable and continuous supply of nitrite. However, the activity of nitrate reductase is often higher than that of nitrite reductase (NIR), making it difficult to accumulate nitrite during the denitrification process. Herein, a strategy for achieving efficient and stable partial denitrification using the biosafe additive dimethyl sulfoxide (DMSO) was constructed, and the mechanism of DMSO inhibiting NIR was analyzed. DMSO addition reduced the expression of NIR gene, and 1% DMSO addition can significantly inhibit NIR enzyme activity to achieve a stable PD process. When the DMSO concentration increased to 3.5%, the NIR enzyme activity was almost inhibited with the enzyme activity of only 0.95 mg nitrite/min. However, the addition of DMSO has almost no inhibitory effect on the nitrate reductase (NAR) enzyme. The affinity constant of DMSO with the NAR enzyme is -2.4 kcal/mol, while the affinity constant of DMSO with the NIR enzyme is as high as -3.1 kcal/mol. DMSO shows a higher affinity for NIR. Moreover, DMSO and nitrite occupy the same catalytic cavity in the NIR enzyme, which is the fundamental reason why DMSO selectively inhibits the NIR enzyme. This study provides a new idea for realizing efficient and stable partial denitrification function.

Fucoidan, the main polysaccharide in various species of brown seaweed, has a high annual production. It is an important source of marine organic carbon and exhibits diverse biological activities and significant application potential. Rhodopirellula sp. P2, a novel marine bacterium of the phylum Planctomycetota, was isolated from intertidal algae samples collected from the Weihai coast, the Yellow Sea, China. The strain P2 is a Gram-negative, aerobic, and pear-shaped bacterium. Here, we report the complete genome sequence of Rhodopirellula sp. P2. The genome of strain P2 consists of a single circular chromosome with 7,291,416 bp and a GC content of 57.38 %, including 5462 protein-coding genes, 2 rRNA genes, and 48 tRNA genes. Genomic analysis revealed that strain P2 possessed 173 CAZymes and 106 sulfatases, indicating that strain P2 has the potential ability to utilize multiple polysaccharides, especially hydrolyze fucoidan to fucose. The genome of strain P2 also encodes a gene cluster related to bacterial microcompartment, suggesting the ability of strain P2 to metabolize fucose. These results enhance the understanding of the diversity and ecological functions of Planctomycetota, and also facilitate the exploitation of Planctomycetota and enzyme resources to utilize fucoidan. This study provides genetic insights into fucoidan catabolism by Planctomycetota, expanding our understanding of fucoidan-degrading microbial groups., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Heat shock proteins 70 KDa (Hsp70s) engage in a broad spectrum of cellular functions in response to various stressors. Marine bivalves face substantial threats from the rising seawater temperature attributed to global warming. In the present study, expression patterns of Hsp70s in Zhikong scallop Chlamys farreri (CfHsp70s) were determined in embryos and larvae at all developmental stages, in healthy adult tissues, and across four various tissues exposed to high temperature for acute and chronic periods through in silico analysis. Spatiotemporal expressions suggested CfHsp70s performed specific functional differentiations in scallop's development and growth. Regulatory expression patterns of CfHsp70s, characterized by predominant down-regulation in the mantle, gill and hemocytes, as well as contrasting up-regulation in the heart, suggest differential functional allocation of CfHsp70s among tissues in response to heat stress. Particularly, a core set of 14 CfHsp70s, especially the nine members of the Hsp70B2s, characterized by gene expansion, intron-less structure, shorter gene length, preference for hydrophilic amino acids, and coordinated expression profiles, was predominantly responsible for the inducible up-regulations observed across all four tissue types. Collectively, the tissue-specific, temporal and core gene-dependent expression patterns of CfHsp70s illustrate the functional allocation and molecular evolution of Hsp70 family members in Zhikong scallops., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Bacteria of the genus Shewanella in the class Gammaproteobacteria are widely distributed in marine environments. Shewanella sp. H8, was isolated from a red algae sample collected from Nelson Island, Antarctica. Here, we present the complete genome sequence of strain H8, which consists of a single circular chromosome comprising 4,490,743 nucleotides with 40.59 % G + C content without any plasmid. In total, 3983 protein coding genes, 95 tRNA genes, and 25 rRNA genes were obtained. Genomic analysis of strain H8 showed that it contains four cold shock proteins and three fatty acid desaturases and possesses the potential to synthesize hglE-KS, arylpolyene, betalactone and RiPP-like compounds. Through genomic annotation, 91 protease-encoding genes were identified within the genome of strain H8. These proteases are classified into six categories based on their catalytic types. Among these proteases, metalloproteinases and serine proteases are dominant. These proteases may provide carbon and nitrogen sources to H8 by degrading proteins in the environment. This study will provide potential genetic information for the future research and development of cold-adapted proteases., Competing Interests: Declaration of competing interest The authors have no financial conflicts of interest to declare., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The pullulan synthetase gene (PUL1), involved in pullulan biosynthesis in Aureobasidium species, remains poorly understood. The open reading frame (ORF) of the PUL1 gene from the high pullulan-producing yeast Aureobasidium melanogenum P16 strain was cloned and characterized. The ORF of the PUL1 gene was determined to be 592 bp in length, encoding 178 amino acid residues. It was observed that an intron of 55 bp disrupted the gene. The promoter of the PUL1 gene contained a CAAT box, a TATA box, and a 5'-HGATAR-3' sequence. The deduced protein possessed a signal peptide comprising 18 amino acids and harbored five potential N-glycosylation sites. Following the disruption of the PUL1 gene in strain P16, the disruptant DP108 yielded 34.7 ± 0.3 g/L of pullulan from sucrose, significantly lower than the production by its wild-type strain P16. This discrepancy underscored the close association between the PUL1 gene and pullulan biosynthesis. The majority of the fused Gfp-Pul1 proteins were found to be localized in the cell membrane and on the surface of vacuoles within the yeast-like fungal cells, indicating that pullulan biosynthesis occurred at these subcellular sites. Following the overexpression of the PUL1 gene, strain G14 produced >72.0 g/L of pullulan from sucrose, surpassing the production of its wild-type counterpart strain P16, which yielded 65.5 g/L of pullulan under the identical conditions. This outcome demonstrated that the overexpression of the PUL1 gene significantly enhanced pullulan production. The apparent molecular mass of the purified pullulan increased to 4.4 × 10 5  Da. As an auxiliary protein, Pul1 was predicted to bind to AmAgs2, the key enzyme in pullulan biosynthesis, facilitating enhanced pullulan production., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The present study evaluated the potential application of free-living marine nematode assemblages as indicators in assessing environmental condition of Jiaozhou Bay (JB), China. Shannon-Wiener diversity (H'), functional trait indices (Index of Trophic Diversity, ITD and Maturity Index, MI) were utilized to rank the benthic habitat quality of the sampled stations. Most of the nematode genera/species belonged to c-p (colonizer-persister) class 2, indicating dominance of opportunistic nematodes and suggesting organic enrichment in the bay. Based on nematode indices, the ecological condition varied from bad to good. Ranking variations were observed among different indices, suggesting different sensitivity of nematode indices to different types of disturbance. Based on the final ecological quality assessment (EcoQ), most sampled stations were ranked as moderate (station J1 was ranked as poor). Nematode indices are more indicative of the influence of land based discharges. For a comprehensive assessment of benthic ecosystem, combined meiofauna and macrofaunal indicators were suggested., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In recent years, microplastics have become a global environmental hot topic of concern. To explore the effects of different concentrations of microplastics on colonization dynamics of periphytic protozoan fauna, a 21-day study was conducted in temperature-controlled circulation systems. Periphytic protozoan communities were used as test organisms and exposed to five concentrations of MPs: 0, 1, 5, 25, and 125 mg l -1 , identification and enumeration were conducted on days 3, 5, 7, 10, 14 and 21. The results showed that the colonization dynamics were driven by MPs and significantly shifted at concentrations over 5 mg l -1 . However, a notable decline in maximum species richness and abundance was observed in the high concentrations of microplastic, along with significant deviations in colonization patterns from the control group (0 mg l -1 ). Therefore, it is suggested that the colonization dynamics of periphytic protozoa can serve as a bioindicator for assessing microplastic concentrations in marine environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Endoscopic submucosal dissection (ESD) is an effective treatment for polyps and early gastrointestinal cancers, but requires a high level of operator skill. Injecting submucosal materials (SIM) helps create a fluid cushion between the mucosal and muscular layers, making the procedure easier and reducing associated risks. However, SIMs commonly used in current clinical practice tend to spread quickly and fail to provide long-lasting submucosal fluid cushions (SFC). Thus, there is a critical need for a material that is easy to inject while also maintaining a durable barrier. We prepared succinylated hydroxybutyl chitosan (HBC-SA) by adding succinic anhydride (SA) to hydroxybutyl chitosan (HBC). The hydrogel had excellent temperature-sensitive properties and was able to be injected via an endoscopic injection needle even after gel formation. In vitro and in vivo studies showed that it has satisfactory biocompatibility. Functional experiments showed that the submucosal lifting properties of this hydrogel were significantly better than that of normal saline (NS) and sodium hyaluronate (SH), two commonly used clinical materials. In addition, the hydrogel possessed excellent hemostatic properties. Based on these results, HBC-SA is a promising candidate for submucosal injection during ESD., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2024. Published by Elsevier B.V.)

Ocean acidification is one of the major global environmental problems facing humankind today, and it has far-reaching impacts on marine organisms and the entire marine ecosystem. Zostera japonica, an important supporting species of intertidal seagrass beds, exhibits high photosynthetic productivity and plays an important role in the carbon cycle of nearshore waters. However, little is known about the characteristics, processes, and mechanisms of its response to ocean acidification. In this study, we conducted a 120-day acidification experiment in Z. japonica; here, plants underwent four leaf regeneration cycles to reveal the response mechanism of Z. japonica to ocean acidification (OA). We found that acidification significantly affected the seedling stage of Z. japonica, impacting leaf regeneration cycles by altering physiological and molecular responses. In one leaf regeneration cycle, the short-term exposure to CO 2 affected the seagrass parameters, such as the regulation of inorganic carbon uptake modes and the regulation of photosynthesis between the dark and light reactions, with the potential to affect the carbon sinks of the marine organisms. The long-term effects on the regulation of antioxidant enzymes and antioxidant metabolites, caused an improvement in the marine life adaptation to OA. In a comparison of the different leaf regeneration cycles, the response pattern of Z. japonica showed an offset of the acidification during the short cycles and an adaption to the acidification during the long cycles. This study revealed the response mechanism of Z. japonica to OA at different time scales and could provide a theoretical basis for accurately assessing the impact of OA on seagrass and the entire seagrass bed ecosystem., Competing Interests: Declaration of competing interest The authors declare no competing interest and no generative AI in scientific writing., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Burns are the fourth most common type of civilian trauma worldwide, and the management of severe irregular scald wounds remains a significant challenge. Herein, crocin-1 laden hydroxybutyl chitosan (CRO-HBC) thermosensitive hydrogel with smart anti-inflammatory performance was developed for accelerating full-thickness burn healing. The injectable and shape adaptability of the CRO-HBC gel make it a promising candidate for effectively filling scald wounds with irregular shapes, while simultaneously providing protection against external pathogens. The CRO-HBC gel network formed by hydrophobic interactions exhibited an initial burst release of crocin-1, followed by a gradual and sustained release over time. The excessive release of ROS and pro-inflammatory cytokines should be effectively regulated in the early stage of wound healing. The controlled release of crocin-1 from the CRO-HBC gel adequately addresses this requirement for wound healing. The CRO-HBC hydrogel also exhibited an excellent biocompatibility, an appropriate biodegradability, keratinocyte migration facilitation properties, and a reactive oxygen species scavenging capability. The composite CRO-HBC hydrogel intelligently mitigated inflammatory responses, promoted angiogenesis, and exhibited a commendable efficacy for tissue regeneration in a full-thickness scalding model. Overall, this innovative temperature-sensitive CRO-HBC injectable hydrogel dressing with smart anti-inflammatory performance has enormous potential for managing severe scald wounds., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Rising ocean temperatures due to global warming pose a significant threat to the bay scallop aquaculture industry. Understanding the mechanisms of thermotolerance in bay scallops is crucial for developing thermotolerant breeds. Our prior research identified Arg0230340.1, part of the positive cofactor 4 (PC4) family, as a key gene associated with the thermotolerance index Arrhenius break temperature (ABT) in bay scallops. Further validation through RNA interference (RNAi) reinforced PC4's role in thermotolerance, offering a solid basis for investigating thermal response mechanisms in these scallops. In this study, we performed a comparative transcriptomic analysis on the temperature-sensitive hearts of bay scallops after siRNA-mediated RNAi targeting Arg0230340.1, to delve into the detailed molecular mechanism of PC4's participation in thermotolerance regulation. The analysis revealed that silencing Arg0230340.1 significantly reduced the expression of mitochondrial tRNA and rRNA, potentially affecting mitochondrial function and the heart's blood supply capacity. Conversely, the up-regulation of genes involved in energy metabolism, RNA polymerase II (RNAPII)-mediated basal transcription, and aminoacyl-tRNA synthesis pathways points to an intrinsic protective response, providing energy and substrates for damage repair and maintenance of essential functions under stress. GO and KEGG enrichment analyses indicated that the up-regulated genes were primarily associated with energy metabolism and spliceosome pathways, likely contributing to myocardial remodeling post-Arg0230340.1 knockdown. Down-regulated genes were enriched in ion channel pathways, particularly those for Na + , K + , and Ca 2+ channels, whose dysfunction could disrupt normal myocardial bioelectric activity. The impaired cardiac performance resulting from RNAi targeting Arg0230340.1 reduced the cardiac workload in scallop hearts, thus affecting myocardial oxygen consumption and thermotolerance. We propose a hypothetical mechanism where PC4 down-regulation impairs cardiac bioelectric activity, leading to decreased thermotolerance in bay scallops, providing theoretical guidance for breeding thermotolerant scallop varieties and developing strategies for sustainable aquaculture in the face of long-term environmental changes., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Antimicrobial peptides (AMPs), derived from a variety of proteins such as ribosomal proteins, play a pivotal role in the innate immune system. However, information regarding ribosomal protein-derived AMPs is currently limited and their mechanisms of action remain poorly defined. Here we identified and characterized the antibacterial activity of amphioxus RPL27 (BjRPL27) and its core functional region located at residues 51-72 (termed BjRPL27 51-72 ). We found that BjRPL27 expression was upregulated in the hepatic caecum following bacterial infection. Both the recombinant protein rBjRPL27 and the synthetic peptide BjRPL27 51-72 effectively killed the Gram-positive bacterium Staphylococcus aureus and the Gram-negative bacterium Aeromonas hydrophila via a combined action of disrupting cell membrane integrity, inducing membrane depolarization, and increasing intracellular reactive oxygen species (ROS) production. Additionally, the sequence of BjRPL27 51-72 was highly conserved among all eukaryotic RPL27s, implying an ancient origin for the antibacterial activity of the RPL27 family. In vivo assays showed that BjRPL27 51-72 not only efficiently protected zebrafish from A. hydrophila infection, but also killed the bacterium S. aureus on the skin wound of rats. Furthermore, neither BjRPL27 nor BjRPL27 51-72 exhibited hemolytic activity towards human red blood cells, making them promising lead molecules for designing novel AMPs. These findings highlight the potential of BjRPL27 51-72 as a novel AMP with selective bactericidal properties., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

RNA-binding proteins are critically involved in the post-transcriptional control of gene expression during embryonic development and in adult life, contributing to regulating cell differentiation and maintaining tissue homeostasis. Compared to the relatively well documented functions of transcription factors, the regulatory roles of RNA-binding proteins in muscle development and function remain largely elusive. However, deficiency of many RNA-binding proteins has been associated with muscular defects, neuromuscular disorders and heart diseases, such as myotonic dystrophy, amyotrophic lateral sclerosis, and cardiomyopathy. Rbm24 is highly conserved among vertebrates and is one of the best characterized RNA-binding proteins with crucial implication in the myogenic and cardiomyogenic programs. It presents the distinctive particularity of displaying highly restricted expression in both skeletal and cardiac muscles, with changes in subcellular localization during the process of differentiation. Functional analyses using different vertebrate models have clearly demonstrated its requirement for skeletal muscle differentiation and regeneration as well as for myocardium organization and cardiac function, by regulating the expression of both common and distinct target genes in these tissues. The challenge remains to decipher the dynamic feature of post-transcriptional circuits regulated by Rbm24 during skeletal myogenesis, cardiomyogenesis, and muscle repair. This review discusses current understanding of its function in striated muscles and its possible implication in human disease, with the aim of identifying research gaps for future investigation., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Substantial amounts of phosphorus are discharged into water bodies, leading to an urgent need to develop methods for phosphorus removal. Here, 12 novel polyphosphate-accumulating organisms were identified from marine biofilms through genomic screening and incorporated into a stable community for phosphorus removal from high-salinity water. The synthetic biofilm community achieved an 82% removal efficiency in a marine broth medium. Electron microscopy showed storage of polyphosphate particles in the bacterial cells. Metatranscriptomic analysis indicated expression changes of genes for phosphate transport, as well as relevant metabolic pathways. In particular, pst genes encoding transporters with high phosphate affinity were downregulated at high-phosphorus concentration, whereas pit genes encoding transporters with low phosphate affinity were constitutively expressed. Furthermore, the synthetic biofilm community exhibited remarkable efficiency in removing over 92% of phosphorus from fish farming facility wastewater. Taken together, synthetic community using marine biofilm bacteria is a new strategy of phosphorus removal., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)