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Abstract Identifying and characterizing virulence proteins secreted by Gram-negative bacteria are fundamental for deciphering microbial pathogenicity as well as aiding the development of therapeutic strategies. Effector predictors utilizing pre-trained protein language models (PLMs) have shown sound performance by leveraging extensive evolutionary and sequential protein features. However, the accuracy and sensitivity of effector prediction remain challenging. Here, we introduce a model named Contrastive-learning of Language Embedding and Biological Features (CLEF) leveraging contrastive learning to integrate PLM representations with supplementary biological features. Biologically information is captured in learned contextualized embeddings to yield meaningful representations. With cross-modality biological features, CLEF outperforms state-of-the-art (SOTA) models in predicting type III, type IV, and type VI secreted effectors (T3SEs/T4SEs/T6SEs) in enteric pathogens. All experimentally verified effectors in Enterohemorrhagic Escherichia coli and 41 of 43 experimentally verified T3SEs of Salmonella Typhimurium are recognized. Moreover, 12 predicted T3SEs and 11 predicted T6SEs are validated by extensive experiments in Edwardsiella piscicida. Furthermore, integrating omics data via CLEF framework enhances protein representations to illustrate effector-effector interactions and determine in vivo colonization-essential genes. Collectively, CLEF provides a blueprint to bridge the gap between in silico PLM’s capacity and experimental biological information to fulfill complicated tasks.

In China, a novel pathogen within the genus Circovirus has been identified as a causative agent of the ‘novel acute hemorrhage syndrome’ (NAHS) in aquacultured populations of turbot (Scophthalmus maximus L.). Histopathological examination using light microscopy revealed extensive necrosis within the cardiac, splenic, and renal tissues of the afflicted fish. Utilizing transmission electron microscopy (TEM), we detected the presence of circovirus particles within the cytoplasm of these cells, with the virions consistently exhibiting a spherical morphology of 20–40 nm in diameter. TEM inspections confirmed the predominance of these virions in the heart, spleen, and kidney. Subsequent molecular characterization through polymerase chain reaction (PCR) analysis corroborated the TEM findings, with positive signals in the aforementioned tissues, in stark contrast to the lack of detection in gill, fin, liver, and intestinal tissues. The TEM observations, supported by PCR electrophoresis data, strongly suggest that the spleen and kidney are the primary targets of the viral infection. Further characterization using biophysical, biochemical assays, and genomic sequencing confirmed the viral classification within the genus Circovirus, resulting in the nomenclature of turbot circovirus (TurCV). The current research endeavors to shed light on the pathogenesis of this pathogen, offering insights into the infection mechanisms of TurCV in this novel piscine host, thereby contributing to the broader understanding of its impact on turbot health and aquaculture.

Many pathogenic bacteria form biofilms that are resistant to not only host immune defenses but also antibiotics, posing a need for the development of strategies to control biofilms. In this study, to prevent biofilm formation of the fulminating foodborne pathogen Vibrio vulnificus, chemical libraries were extensively screened to identify a small molecule inhibiting the activity of BrpR, a transcriptional regulator for biofilm genes. Accordingly, the BrpR inhibitor BFstatin [N1-(2-chloro-5-fluorophenyl)-N3-propylmalonamide], with a half-maximal effective concentration of 8.01 μM, was identified. BFstatin did not interfere with bacterial growth or exhibit cytotoxicity to the human epithelial cell line. BFstatin directly bound to BrpR and interrupted its binding to the target promoter DNAs of the downstream genes. Molecular dynamics simulation of the interaction between BFstatin and BrpR proposed that BFstatin modifies the structure of BrpR, especially the DNA-binding domain. Transcriptomic analyses revealed that BFstatin reduces the expression of the BrpR regulon including the cabABC operon and brp locus which contribute to the production of biofilm matrix of V. vulnificus. Accordingly, BFstatin diminished the biofilm levels of V. vulnificus by inhibiting the matrix development in a concentration-dependent manner. Altogether, BFstatin could be an anti-biofilm agent targeting BrpR, thereby rendering V. vulnificus more susceptible to host immune defenses and antibiotics.

With the rapid development of the aviation industry, the impact of contrails on global warming is becoming increasingly significant. However, due to limitations in sensor technology and data sources, precise, all-weather observations of contrails remain a significant challenge. To address this, this study utilizes thermal imagery data from the SDGSAT-1 to classify newly formed contrails based on their length, creating SDGCONTR, the first three-band thermal infrared contrail dataset with a 30-meter spatial resolution. Based on this dataset, we propose an effective contrail image classification method: the SDGContrail Images Classification Method. This method builds on the existing Multi-axis Vision Transformer deep learning model. In the preprocessing stage, it employs an innovative contrail enhancement method by creating masks based on contrail brightness temperature and brightness temperature ratio percentiles in thermal infrared images. Our method achieved optimal classification performance compared to other methods, with the F1 Score of 95.2%. Using this model, we further analyzed the geographic and diurnal distribution patterns of long and short contrails, validating the mechanism of contrail formation. Our method not only enhances the ability to conduct large-scale, all-weather, and detailed contrail observations, but also sets a new standard for environmental monitoring and aviation safety.

Aeromonas salmonicida is a common pathogen of salmonid fishes that poses a significant threat to the fresh water and marine culture industry, potentially resulting in huge economic losses. To prevent and control fish diseases caused by A. salmonicida, rapid and effective diagnostic approaches must be developed, and which are important for routine monitoring and clinical care. By combining recombinase polymerase amplification (RPA) technology with a visible lateral flow strip (RPA-LF), we have enhanced both the precision of RPA detection and the convenience of real-time monitoring. In this study, we introduce a robust method for detecting A. salmonicida using RPA-LF. This assay specifically targets the ASA_1441 gene of A. salmonicida, ensuring high specificity, without cross-reactivity with other prevalent fresh water or marine pathogens. The optimal amplification temperature of the RPA assay was 39 ​°C. Its sensitivity extends to as low as 100 ​fg of purified DNA, representing more than 1000-fold higher sensitivity than conventional PCR methods. Furthermore, to enhance the usability of the RPA-LF assay, we developed a rapid sample preparation method using cellulose dipsticks for nucleic acid extraction. This method achieves a limit of detection (LOD) as low as 1.67 ​CFU/μL and completes the entire process within 20 ​min. In conclusion, our findings present a rapid and precise tool for monitoring A. salmonicida infection in aquaculture and marine culture. This advancement offers valuable insights for effective disease prevention and control strategies.

Abstract Modulation of cell death is a powerful strategy employed by pathogenic bacteria to evade host immune clearance and occupy profitable replication niches during infection. Intracellular pathogens employ the type III secretion system (T3SS) to deliver effectors, which interfere with regulated cell death pathways to evade immune defenses. Here, we reveal that poly(ADP-ribose) polymerase-1 (PARP1)-dependent cell death restrains Edwardsiella piscicida’s proliferation in mouse monocyte macrophages J774A.1, of which PARP1 activation results in the accumulation of poly(ADP-ribose) (PAR) and enhanced inflammatory response. Moreover, E. piscicida, an important intracellular pathogen, leverages a T3SS effector YfiD to impair PARP1’s activity and inhibit PAR accumulation. Once translocated into the host nucleus, YfiD binds to the ADP-ribosyl transferase (ART) domain of PARP1 to suppress its PARylation ability as the pharmacological inhibitor of PARP1 behaves. Furthermore, the interaction between YfiD and ART mainly relies on the complete unfolding of the helical domain, which releases the inhibitory effect on ART. In addition, YfiD impairs the inflammatory response and cell death in macrophages and promotes in vivo colonization and virulence of E. piscicida. Collectively, our results establish the functional mechanism of YfiD as a potential PARP1 inhibitor and provide more insights into host defense against bacterial infection.

The herbaceous peony (Paeonia lactiflora Pall.) plant is world-renowned for its ornamental, medicinal, edible, and oil values. As global warming intensifies, its growth and development are often affected by high-temperature stress, especially in low-latitude regions. Superoxide dismutase (SOD) is an important enzyme in the plant antioxidant systems and plays vital roles in stress response by maintaining the dynamic balance of reactive oxygen species (ROS) concentrations. To reveal the members of then SOD gene family and their potential roles under high-temperature stress, we performed a comprehensive identification of the SOD gene family in the low-latitude cultivar ‘Hang Baishao’ and analyzed the expression patterns of SOD family genes (PlSODs) in response to high-temperature stress and exogenous hormones. The present study identified ten potential PlSOD genes, encoding 145–261 amino acids, and their molecular weights varied from 15.319 to 29.973 kDa. Phylogenetic analysis indicated that PlSOD genes were categorized into three sub-families, and members within each sub-family exhibited similar conserved motifs. Gene expression analysis suggested that SOD genes were highly expressed in leaves, stems, and dormancy buds. Moreover, RNA-seq data revealed that PlCSD1-1, PlCSD3, and PlFSD1 may be related to high-temperature stress response. Finally, based on the Quantitative Real-time PCR (qRT-PCR) results, seven SOD genes were significantly upregulated in response to high-temperature stress, and exogenous EBR and ABA treatments can enhance high-temperature tolerance in P. lactiflora. Overall, these discoveries lay the foundation for elucidating the function of PlSOD genes for the thermotolerance of herbaceous peony and facilitating the genetic breeding of herbaceous peony cultivars with strong high-temperature resistance.

Stripe noise is present in the on-orbit images captured by the Sustainable Development Goals Satellite-1 (SDGSAT-1) Thermal Infrared Spectrometer (TIS). Removing these stripes lays the crucial groundwork for subsequent remote sensing data applications. This paper proposes a high-performance method for removing stripe noise in SDGSAT-1 TIS large dynamic range imaging. Based on the fixation properties of the stripe noise, we utilize the a priori information to enhance the gradient variation around the stripe region. This step successfully separates the background from the noise and speeds up the noise extraction. We extract local thresholds from the central difference matrix using an adaptive threshold extraction method based on the Maximum Interclass Variance (OTSU). To maximize the retention of image details, we combine structural information about stripe positions with a weighted filter kernel based on the L2 norm to predict noise digital number (DN). The proposed method extensively experiments with simulated and on-orbit data in different scenarios. It has the best overall performance in qualitative evaluation, quantitative evaluation, processing speed, and robustness.

BackgroundHeavy metal pollution has become a global problem, which urgently needed to be solved owing to its severe threat to water ecosystems and human health. Thus, the exploration and development of a simple, cost-effective and environmental-friendly technique to remove metal elements from contaminated water is of great importance. Algae are a kind of photosynthetic autotroph and exhibit excellent bioadsorption capacities, making them suitable for wastewater treatment.MethodsThe effects of heavy metals (copper, lead and cadmium) on the growth, biomolecules accumulation, metabolic responses and antioxidant response of Dunaliella salina were investigated. Moreover, the Box-Behnken design (BBD) in response surface methodology (RSM) was used to optimize the biosorption capacity, and FT-IR was performed to explore the biosorption mechanism of D. salina on multiple heavy metals.ResultsThe growth of D. salina cells was significantly inhibited and the contents of intracellular photosynthetic pigments, polysaccharides and proteins were obviously reduced under different concentrations of Cu2+, Pb2+ and Cd2+, and the EC50 values were 18.14 mg/L, 160.37 mg/L and 3.32 mg/L at 72 h, respectively. Besides, the activities of antioxidant enzyme SOD and CAT in D. salina first increased, and then descended with increasing concentration of three metal ions, while MDA contents elevated continuously. Moreover, D. salina exhibited an excellent removal efficacy on three heavy metals. BBD assay revealed that the maximal removal rates for Cu2+, Pb2+, and Cd2+ were 88.9%, 87.2% and 72.9%, respectively under optimal adsorption conditions of pH 5-6, temperature 20-30°C, and adsorption time 6 h. Both surface biosorption and intracellular bioaccumulation mechanisms are involved in metal ions removal of D. salina. FT-IR spectrum exhibited the main functional groups including carboxyl (-COOH), hydroxyl (-OH), amino (-NH2), phosphate (-P=O) and sulfate (-S=O) are closely associated with the biosorption or removal of heavy metalsions.DiscussionAttributing to the brilliant biosorption capacity, Dunaliella salina may be developed to be an excellent adsorbent for heavy metals.

Edwardsiella species in aquatic environments exist either as individual planktonic cells or in communal biofilms. These organisms encounter multiple stresses, include changes in salinity, pH, temperature, and nutrients. Pathogenic species such as E. piscicida, can multiply within the fish hosts. Additionally, Edwardsiella species (E. tarda), can carry antibiotic resistance genes (ARGs) on chromosomes and/or plasmids, that can be transmitted to the microbiome via horizontal gene transfer. E. tarda serves as a core in the aquatic resistome. Edwardsiela uses molecular switches (RpoS and EsrB) to control gene expression for survival in different environments. We speculate that free-living Edwardsiella can transition to host-living and vice versa, using similar molecular switches. Understanding such transitions can help us understand how other similar aquatic bacteria switch from free-living to become pathogens. This knowledge can be used to devise ways to slow down the spread of ARGs and prevent disease outbreaks in aquaculture and clinical settings.

ABSTRACT Although antibiotics are the primary method against bacterial infections, the rapid emergence of antibiotic resistance has forced interest in alternative antimicrobial strategies. Phage has been considered a new biological antimicrobial agent due to its high effectiveness in treating bacterial infections. However, the applications of phage therapy have been limited by the quick development of phage-resistant bacteria. Therefore, more effective phage treatment strategies need to be explored guided by characterizing phage-resistant mutants. In this study, Pseudomonas plecoglossicida phage vB_PpS_SYP was isolated from the sewage but exhibited weak antibacterial activity caused by phage-resistant bacteria. Phage-resistant mutants were isolated and their whole genomes were analyzed for differences. The results showed that mutations in glycosyltransferase family 1 (GT-1) and hypothetical outer membrane protein (homP) led to bacterial phage resistance. The GT-1 mutants had lower biofilm biomass and higher antibiotic sensitivity than wild-type strain. Phage SYP evolved a broader host range and improved antimicrobial efficacy to infect homP mutants. Therefore, we designed a strategy for combined antibiotic and evolved phage inhibition driven by the two phage-resistant mutants. The results showed that the combination was more effective against bacteria than either antibiotics or phage alone. Our findings presented a novel approach to utilizing poorly antimicrobial phages by characterizing their phage-resistant mutants, with the potential to be expanded to include phage therapy for a variety of pathogens. IMPORTANCE The rapid emergence of antibiotic resistance renews interest in phage therapy. However, the lack of efficient phages against bacteria and the emergence of phage resistance impaired the efficiency of phage therapy. In this study, the isolated Pseudomonas plecoglossicida phage exhibited poor antibacterial capacity and was not available for phage therapy. Analysis of phage-resistant mutants guided the design of antibacterial strategies for the combination of antibiotics with evolved phages. The combination has a good antibacterial effect compared to the original phage. Our findings facilitate ideas for the development of antimicrobial-incapable phage, which have the potential to be applied to the phage treatment of other pathogens.

In vertebrates, bony fishes possess not only innate immune cells but also T and B cells that are equivalent to those in mammals. However, the precise sub-cluster of immune cells in teleost fish remains largely unknown. Herein, we developed a dynamic bacterial infection model in turbot (Scophthalmus maximus) and created a fish immune cell landscape (FICL) for a primary lymphoid organ (head kidney), a secondary lymphoid organ (spleen), and barrier tissues (gills and posterior intestine). Moreover, through comprehensive characterization of the expression profiles of 16 clusters, including dendritic cells-like (DCs-like), macrophages (MΦs), neutrophils, NK cells, as well as 12 sub-clusters of T and B cells, we found that CD8+ CTLs, CD4−CD8− T, Th17 and ILC3-2 like cells possess a bifunctional role associated with cytotoxicity and immunoregulation during bacterial infection. To our knowledge, these results could provide a useful resource for a better understanding of immune cells in teleost fish and could act as a comprehensive knowledge base for assessing the evolutionary mechanism of adaptive immunity in vertebrates.

There are multiple seismic fault zones near Xi’an in China, among which the Li Piedmont Fault has multiple slip surfaces. A 3D finite element dynamic Soil–Fault–Tunnel model was established based on the engineering background of the Xi’an Metro tunnel orthogonally crossing the Li Piedmont Fault. The input seismic loads used the Chi-Chi, El-Centro, and artificial seismic waves, and the latter was artificially synthesized based on seismic conditions and site conditions of actual engineering. The Chi-Chi seismic wave with larger PGV/PGA and wider acceleration-sensitive area is a near-field seismic wave, while the others are far-field seismic waves. The seismic loads were transformed into the equivalent nodal force on the boundary nodes of the model, and nonlinear dynamic calculation was carried out to obtain the longitudinal seismic response of the structure. The main results show that the fault amplifies the seismic response of the tunnel, and the tunnel at the position of the fault slip surfaces is more vulnerable to failure, especially near the slip surface between the hanging wall and the fault, where the maximum acceleration, soil pressure, and internal force of the tunnel structure occur. In addition, the seismic response of the tunnel and soil caused by near-field seismic motion is significantly stronger than that caused by far-field seismic motion.

Buried pipelines are commonly damaged when laid across strike-slip faults, always leading to some level of destruction with fault movement. The moment of the neutral axis of a pipe section was obtained by integration, and the equations for the bending moment and the bending strain on a pipeline’s section were presented here, based on a trilinear stress–strain model. The calculation method for the lateral soil pressure and pipeline’s bending strain near the fault-crossing point was improved. Lateral soil pressure was regarded as being related to lateral pipeline movement and, for accurate calculation, this part of the pipeline was divided into finite element segments. An iterative process for solving for pipe bending strain was derived, and the algorithm and program for calculating bending strain and the potential damage position of the pipeline’s sections was compiled based on Matlab software. Compared with finite element method (FEM) results and the current standard method, in the situation of a pipeline being in tension under the action of a strike-slip fault (intersection angle

Turbot (Scophthalmus maximus) is an important commercial fish in China that can be infected by a series of bacterial pathogens, leading to great economic losses. In this study we focused on the epidemiology of turbot bacterial diseases in the major farming areas in China for three years. A total of 155 cases with 446 diseased turbots were investigated, and dominant bacterial pathogens were isolated from 137 cases (344 turbots). Thus, bacteria are the major threat to farming turbot in China. Edwardsiella piscicida was the major pathogen, which isolated as the dominant colony in 62 cases (40.00%) with 151 turbots (33.85%). Aeromonas salmonicida was isolated in 57 cases (36.77%) with 116 turbots (26.01%). Vibrio anguillarum was isolated in nine cases (5.81%), and Streptococcus parauberis in five cases (3.23%). Photobacterium damselae and Mycobacterium marinum were also isolated from one or two diseased fish. Other Vibrio spp. were isolated in 15 cases (9.68%). Two species of pathogen were isolated in 13 cases, and three species (E. piscicida, A. salmonicida, and S. parauberis) in one case. In 19 cases, no bacteria were isolated. Based on the annual disease analysis, we found that the E. piscicida infection proportion of total cases was greatly decreased, which may be caused by the attenuated vaccine inoculated in 2018. The antibiotic resistance of E. piscicida strains isolated in Weifang city was also determined. We found that the resistance to ceftriaxone, doxycycline, and SMZ/TMP were significantly increased from October 2016 to June 2018, and all the E. piscicida isolates exhibited resistance to SMZ/TMP in June 2018. These results indicated that E. piscicida is the major threat to turbot farming in China, and the attenuated E. piscicida vaccine exhibits effective protection. The usage of antibiotics may induce resistance quickly. Thus, development of vaccines is an important work for sustainable development of turbot farming in the future.

Soil salinization and acidification seriously damage soil health and restricts the sustainable development of planting. Excessive application of chemical fertilizer and other reasons will lead to soil acidification and salinization. This study focus on acid and salinized soil, investigated the effect of phosphate-solubilizing bacteria, Aspergillus niger MJ1 combined with nitrogen-fixing bacteria Pseudomonas stutzeri DSM4166 or mutant Pseudomonas fluorescens CHA0-nif on crop quality, soil physicochemical properties, and microbial communities. A total of 5 treatments were set: regular fertilization (T1), regular fertilization with MJ1 and DSM4166 (T2), regular fertilization with MJ1 and CHA0-nif (T3), 30%-reducing fertilization with MJ1 and DSM4166 (T4), and 30%-reducing fertilization with MJ1 and CHA0-nif (T5). It was found that the soil properties (OM, HN, TN, AP, AK, and SS) and crop quality of cucumber (yield production, protein, and vitamin C) and lettuce (yield production, vitamin C, nitrate, soluble protein, and crude fiber) showed a significant response to the inoculated strains. The combination of MJ1 with DSM4166 or CHA0-nif influenced the diversity and richness of bacterial community in the lettuce-grown soil. The organismal system-, cellular process-, and metabolism-correlated bacteria and saprophytic fungi were enriched, which were speculated to mediate the response to inoculated strains. pH, OM, HN, and TN were identified to be the major factors correlated with the soil microbial community. The inoculation of MJ1 with DSM4166 and CHA0-nif could meet the requirement of lettuce and cucumber growth after reducing fertilization in acid and salinized soil, which provides a novel candidate for the eco-friendly technique to meet the carbon-neutral topic.

Fucoxanthin is the most abundant marine carotenoid derived from edible brown seaweeds and has been used as a functional ingredient for the treatment of obesity. However, poor brain bioavailability of fucoxanthin has limited its application in combating neurological diseases. In this study, we demonstrated that 40 % fucoxanthin was released from polylactic-co-glycolic acid-polyethylene glycol (PLGA-PEG) nanoparticles at one day after incubation. Fucoxanthin nanoparticles (20–40 mg/kg, i.v.) significantly prevented neurological and behavioral deficits in middle cerebral artery occlusion/reperfusion (MCAO)-treated rats via the reduction of M1 microglial activation, decrease of pro-inflammatory factor production, inactivation of the nuclear factor-κB (NF-κB) pathway, and elevation of the nuclear factor-E2-related factor 2 (Nrf2) pathway in ischemic penumbra. Moreover, fucoxanthin nanoparticles (5–15 μg/mL) inhibited hypoxia-stimulated neurotoxicity in a mouse hippocampal neuron cell line (HT22 cells). These results suggest that fucoxanthin nanoparticles enhanced brain bioavailability and produced neuroprotection against ischemic stroke in vivo with much lower effective concentrations than fucoxanthin itself, providing further support for the development of fucoxanthin as a functional ingredient for the prevention of ischemic stroke with proper nanoparticle formulations.

Postoperative cognitive dysfunction (POCD) is a clinical syndrome characterizing by cognitive impairments in the elderly after surgery. There is limited effective treatment available or clear pathological mechanisms known for this syndrome. In this study, a Connectivity Map (CMap) bioinformatics model of POCD was established by using differently expressed landmark genes in the serum samples of POCD and non-POCD patients from the only human transcriptome study. The predictability and reliability of this model were further supported by the positive CMap scores of known POCD inducers and the negative CMap scores of anti-POCD drug candidates. Most retinoic acid receptor (RAR) agonists were negatively associated with POCD in this CMap model, suggesting that RAR might be a novel target for POCD. Most importantly, acitretin, a clinically used RAR agonist, significantly inhibited surgery-induced cognitive impairments and prevented the reduction in RARα and RARα-target genes in the hippocampal regions of aged mice. The study denotes a reliable CMap bioinformatics model of POCD for future use and establishes that RAR is a novel therapeutic target for treating this clinical syndrome.

As a typical dioecious species, Zanthoxylum armatum establishes apomictic reproduction, hence only female trees are cultivated. However, male and hermaphrodite flowers have recently appeared in female plants, resulting in a dramatic yield reduction. To date, the genetic basis underlying sex determination and apomixis in Z. armatum has been largely unknown. Here, we observed abortion of the stamen or carpel prior to primordium initiation, thus corroborating the potential regulation of MADS-box in sex determination. In Z. armatum, a total of 105 MADS-box genes were identified, harboring 86 MIKC-type MADSs with lack of FLC orthologues. Transcriptome analysis revealed candidate MADSs involved in floral organ identity, including ten male-biased MADSs, represented by ZaMADS92/81/75(AP3/PI-like), and twenty-six female-specified, represented by ZaMADS80/49 (STK/AGL11-like) and ZaMADS42 (AG-like). Overexpressing ZaMADS92 resulted in earlier flowering, while ZaMADS80 overexpression triggered precocious fruit set and parthenocarpy as well as dramatic modifications in floral organs. To characterize their regulatory mechanisms, a comprehensive protein-protein interaction network of the represented MADSs was constructed based on yeast two-hybrid and bimolecular fluorescence complementation assays. Compared with model plants, the protein interaction patterns in Z. armatum exhibited both conservation and divergence. ZaMADS70 (SEP3-like) interacted with ZaMADS42 and ZaMADS48 (AP3-like) but not ZaMADS40 (AP1-like), facilitating the loss of petals in Z. armatum. The ZaMADS92/ZaMADS40 heterodimer could be responsible for accelerating flowering in ZaMADS92-OX lines. Moreover, the interactions between ZaMADS80 and ZaMADS67(AGL32-like) might contribute to apomixis. This work provides new insight into the molecular mechanisms of MADS-boxes in sex organ identity in Z. armatum.

Alzheimer's disease (AD) is an irreversible neurodegenerative disorder, which is pathologically characterized by the deposits of β-amyloid (Aβ), and plays an important role in neuronal death. Indirubin-3′-monoxime (I3M) showed neuroprotective effects against Aβ-induced neuronal apoptosis. However, the use of I3M in AD treatment is limited due to its low bioavailability. Herein, PLGA-PEG nanoparticles were synthesized for I3M loading. I3M could release sustainedly sustain release from the I3M-loaded PLGA-PEG nanoparticles (PLGA-PEG-I3M NPs) without obvious burst release. What's more, the PLGA-PEG-I3M NPs could significantly promote the uptake of I3M by PC12 ​cells through nanoparticle-mediated transport, and improve the efficacy of I3M on the inhibition of Aβ fibrillization and oligomerization as well as the neuroprotective activity of I3M on Aβ oligomers-induced neuronal death. Thus, the PLGA-PEG-I3M NPs may be a promising platform for AD therapy.

In this work, hydrothermal pretreatment (autohydrolysis) was coupled with endo-xylanase enzymatic hydrolysis for bamboo shoot shell (BSS) to produce glucose and valuable xylooligosaccharides (XOS) rich in xylobiose (X2) and xylotriose (X3). Results showed that the enzymatic hydrolysis efficiency of pretreated BSS residue reached 88.4% with addition of PEG during the hydrolysis process. To enrich the portions of X2–X3 in XOS, endo-xylanase was used to hydrolyze the XOS in the prehydrolysate, which was obtained at the optimum condition (170°C, 50 min). After enzymatic hydrolysis, the yield of XOS reached 25.6%, which contained 76.7% of X2–X3. Moreover, the prehydrolysate contained a low concentration of fermentation inhibitors (formic acid 0.7 g/L, acetic acid 2.6 g/L, furfural 0.7 g/L). Based on mass balance, 32.1 g of glucose and 6.6 g of XOS (containing 5.1 g of X2-X3) could be produced from 100.0 g of BSS by the coupled technology. These results indicate that BSS could be an economical feedstock for the production of glucose and XOS.

Vibrio parahaemolyticus causes seafood-borne diarrheal diseases. Here, the authors show that the pathogen uses a histidine kinase to sense host-derived nitrite and downregulate a proinflammatory type 3 secretion system, thus enhancing intestinal colonization and virulence.

Edwardsiella piscicida is one of the important pathogens in aquaculture, which takes huge losses to the economic benefits of turbot industry. Thus, a simple, rapid and accurate diagnostic assay of E. piscicida becomes an urgent need. In the present study, a detection method of E. piscicida based on recombinase polymerase amplification combined with lateral flow strip (RPA-LF) was established. The RPA-LF assay targeted E. piscicida evpP gene and could detect as low as 10 fg DNA of E. piscicida, which was approximately 1000 times more sensitive than conventional PCR assay. Meanwhile, the RPA-LF assay showed no cross-reactivity with DNA from other major bacterial pathogens in aquaculture. Besides, to improve the convenience of RPA-LF assay, a rapid on-the-spot sample preparation using nucleic acid extraction by cellulose dipsticks was established. Results indicated that bacteria could be detected as low as 1 copy and completed within 30 min. Moreover, this modified RPA-LF assay could be used to monitor E. piscicida infection in turbot industry.

Grammatical gender presents persistent difficulty for adult learners of Spanish in L2 acquisition; however, there is a literature gap in L3 acquisition of gender, specifically of typologically different languages. In this project, we investigate the acquisition of Spanish gender agreement by Russian (L1)/Mandarin (L1)-English (L2) speakers of Spanish (L3) and compare the findings with English(L1) speakers of Spanish (L2). Studying these languages is particularly interesting because some exhibit an explicit gender system (Spanish and Russian) while others do not (English and Mandarin). In order to examine the effect of L1/L2 influence of these languages on L3 Spanish acquisition, 55 participants completed two tasks: a picture identification task and a grammaticality judgement task. Results indicate that advanced learners of Spanish of all L1 backgrounds performed at or near ceiling. All beginner learners performed better with canonically marked masculine nouns than noncanonical feminine nouns, thus corroborating previous findings. Regarding L1 influence, Russian participants outperformed the other two groups, especially in Task 1 (Picture Identification), thereby indicating that they may be transferring to some degree the grammatical gender system of their L1. Overall, this research provides evidence that multiple factors, including structural typology and L3 proficiency level, play a role in L3 acquisition.

Summary: Bacterial pathogens are thought to activate expression of virulence genes upon detection of host-associated cues, but identification of the nature of such signals has proved difficult. We generated a genome-scale defined transposon mutant library in Edwardsiella piscicida, an important fish pathogen, to quantify the fitness of insertion mutants for intracellular growth in macrophages and in turbot (Scophthalmus maximus). These screens identified EvrA, a transcription activator that induces expression of esrB, a key virulence regulator. EvrA is directly bound and activated by mannose-6-phosphate (man-6P) derived from actively imported mannose. Mutants lacking EvrA or expressing an EvrA unable to bind man-6P were similarly attenuated in turbot. Exogenously added mannose promoted E. piscicida virulence, and high levels of mannose were detected in fish tissue. Together, these observations reveal that binding of a host-derived sugar to a transcription factor can facilitate pathogen sensing of the host environment and trigger virulence programs. : Pathogenic Organism; Microbiology; Fish Culture Subject Areas: Pathogenic Organism, Microbiology, Fish Culture

Abstract Background Pichia pastoris (syn. Komagataella phaffii) is a widely used generally recognized as safe host for heterologous expression of proteins in both industry and academia. Recently, it has been shown to be a potentially good chassis host for the production of high-value pharmaceuticals and chemicals. Nevertheless, limited availability of selective markers and low efficiency of homologous recombination make this process difficult and time-consuming, particularly in the case of multistep biosynthetic pathways. Therefore, it is crucial to develop an efficient and marker-free multiloci gene knock-in method in P. pastoris. Results A non-homologous-end-joining defective strain (Δku70) was first constructed using the CRISPR–Cas9 based gene deficiency approach. It was then used as a parent strain for multiloci gene integration. Ten guide RNA (gRNA) targets were designed within 100 bp upstream of the promoters or downstream of terminator, and then tested using an eGFP reporter and confirmed as suitable single-locus integration sites. Three high-efficiency gRNA targets (P AOX1 UP-g2, P TEF1 UP-g1, and P FLD1 UP-g1) were selected for double- and triple-locus co-integration. The integration efficiency ranged from 57.7 to 70% and 12.5 to 32.1% for double-locus and triple-locus integration, respectively. In addition, biosynthetic pathways of 6-methylsalicylic acid and 3-methylcatechol were successfully assembled using the developed method by one-step integration of functional genes. The desired products were obtained, which further established the effectiveness and applicability of the developed CRISPR–Cas9-mediated gene co-integration method in P. pastoris. Conclusions A CRISPR–Cas9-mediated multiloci gene integration method was developed with efficient gRNA targets in P. pastoris. Using this method, multiple gene cassettes can be simultaneously integrated into the genome without employing selective markers. The multiloci integration strategy is beneficial for pathway assembly of complicated pharmaceuticals and chemicals expressed in P. pastoris.