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Bacterial nanocellulose (BNC) currently has emerged as a potential biopolymer that can be used for various industrial applications. However, the major concern is the limitation of the bacteria used for BNC production on a larger scale. This study aimed to isolate and identify potential nanocellulose-producing bacteria from pineapple wastes. In this study, 11 isolates were screened and the F1 isolate, which produced the highest BNC yield was chosen for 16S rRNA sequencing. Based on the 16S rRNA analysis, Comamonas terrae YSZ sp. (OQ592726.1) was the best BNC producer with 1.68 ± 0.19 g/L yield. The physicochemical characteristics from FESEM analysis revealed that C. terrae YSZ sp. produced amorphous BNC, with fewer nanofibrils. The XRD analysis showed that the BNC produced had a 19.3% of crystallinity index. To the best of our knowledge, this is the first work reporting the isolation of C. terrae YSZ sp. from pineapple wastes with more amorphous regions providing an interesting alternative for heavy metal removal potentials. [ABSTRACT FROM AUTHOR]

Background: This meta-analysis explores alterations in the gut microbiota of patients with Multiple Sclerosis (MS) using 16S ribosomal RNA (rRNA) gene sequencing. Methods: Adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, our comprehensive review spanned major databases, including PubMed, Web of Science, Embase, Cochrane, and Ovid, targeting observational studies that implemented 16S rRNA gene sequencing on fecal specimens. The quality of these studies was meticulously evaluated using the Newcastle-Ottawa scale. Results: Our search yielded 26 relevant studies conducted between 2015-2022, encompassing 2885 participants. No significant differences were observed in alpha diversity indices (Shannon, Chao1, Operational Taxonomic Units (OTU), and Simpson) between MS patients and controls in general. Nonetheless, subgroup analyses according to disease activity using the Shannon index highlighted a significant decrease in microbial diversity during MS's active phase. Similarly, an evaluation focusing on MS phenotype revealed diminished diversity in individuals with relapsing-remitting MS (RRMS). Microbial composition analysis revealed no consistent increase in pro-inflammatory Bacteroidetes or decrease in anti-inflammatory Firmicutes within the MS cohort. Conclusion: The gut microbiome's role in MS presents a complex panorama, where alterations in microbial composition might hold greater significance to disease mechanisms than diversity changes. The impact of clinical factors such as disease activity and phenotype are moderately significant, underscoring the need for further research to elucidate these relationships. Prospective research should employ longitudinal methodologies to elucidate the chronological interplay among gut microbiota, disease evolution, and therapeutic strategies. [ABSTRACT FROM AUTHOR]

Fragilariaceae is a paraphyletic family of araphid diatoms commonly used as bio-indicators, in environmental assessments and in paleoenvironmental reconstructions, and with various potential industrial applications. Recent molecular taxonomic research has highlighted significant limitations in traditional morphology-based investigations of these diatom species. Most descriptions of species and genera of the Fragilariaceae present broad morphological character definitions and many diagnostic characters are indistinguishable by light microscopy. In this sense, taxon misidentification is common and could have serious implications for environmental surveys and laboratory experiments. To better understand the diversity of the Fragilariaceae, we (1) performed phylogenetic analyses of the small subunit ribosomal RNA (18S rRNA), rbcL and psbC gene sequences, (2) inferred a cladogram from key morphological features used in the traditional identification of Fragilariaceae, (3) tested if the topologies of the tree recovered from the molecular phylogeny, of the tree based on morphology and of the trees constraining to monophyly the genera Sarcophagodes, Pseudostaurosira and Nanofrustulum (together and separately) were significantly different and (4) mapped morphological character states on the ML tree and inferred their evolution based on maximum parsimony. Our results supported the monophyly of a group of Fragilariaceae within small araphid diatoms including the genera Cratericulifera, Plagiostriata, Castoridens, Opephora, Staurosira, Staurosirella, Punctastriata, Psammotaenia,Hendeyella, Stauroforma, Pseudostaurosira sensu Li, Nanofrustulum sensu Li, Serratifera sensu Li and Gedaniella sensu Li. Molecular phylogeny and topology tests suggested that the latest circumscriptions of the genera Sarcophagodes, Pseudostaurosira and Nanofrustulum sensu Morales were not monophyletic. Analyses of the Antarctic strain IMA070A collected during the XXXIV Italian Antarctic Expedition using fine structural features of the frustule and molecular data revealed that this diatom belongs to a distinct lineage within Gedaniella, which we describe here as Gedaniella antarctica sp. nov. Highlights: Fragilariaceae diversity was revealed combining molecular data and morphology. Fragilariaceae displayed cryptic diversity. Gedaniella antarctica represent a new araphid diatom from Antarctica. [ABSTRACT FROM AUTHOR]

BACKGROUND: Microbiota succession determines the flavor and quality of fermented foods. Quantitative PCR‐based quantitative microbiome profiling (QMP) has been applied broadly for microbial analysis from absolute abundance perspectives, transforming microbiota ratios into counts by normalizing 16S ribosomal RNA (16S rRNA) gene sequencing data with gene copies quantified by quantitative PCR. However, the application of QMP in fermented foods is still limited. RESULTS: QMP elucidated microbial succession of Taiwanese pickled cabbage. In the spontaneous first‐round fermentation (FR), the 16S rRNA gene copies of total bacteria increased from 6.1 to 10 log copies mL−1. The dominant lactic acid bacteria genera were successively Lactococcus, Leuconostoc and Lactiplantibacillus. Despite the decrease in the proportion of Lactococcus during the succession, the absolute abundance of Lactococcus still increased. In the backslopping second‐round fermentation (SR), the total bacteria 16S rRNA gene copies increased from 7.6 to 9.9 log copies mL−1. The addition of backslopping starter and vinegar rapidly led to a homogenous microbial community dominated by Lactiplantibacillus. The proportion of Lactiplantibacillus remained consistently around 90% during SR, whereas its absolute abundance exhibited a continuous increase. In SR without vinegar, Leuconostoc consistently dominated the fermentation. CONCLUSION: The present study highlights that compositional analysis would misinterpret microbial dynamics, whereas QMP reflected the real succession profiles and unveiled the essential role of vinegar in promoting Lactiplantibacillus dominance in backslopping fermentation of Taiwanese pickled cabbage. Quantitative microbiome profiling (QMP) was found to be a more promising approach for the detailed observation of microbiome succession in food fermentation compared to compositional analysis. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Four Gram-stain-positive bacterial strains (designated 475-2T, 46-6BT, 778-2T and A810-3), isolated from traditional Chinese pickle, were characterized using a polyphasic taxonomic approach. Strain 475-2T was most closely related to the type strain of Lapidilactobacillus achengensis, having 99.9% 16S rRNA gene sequence similarity, 94.1–95.1% average nucleotide identity (ANI) and 57.6% digital DNA–DNA hybridization (dDDH) values. Strain 46-6BT was most closely related to the type strain of Secundilactobacillus similis, having 99.8% 16S rRNA gene sequence similarity, 94.3–94.9% ANI and 58.9–59.2% dDDH values. Strains 778-2T and A810-3 were phylogenetically related to the type strains of Streptococcus salivarius, Streptococcus thermophilus and Streptococcus vestibularis, having 99.7–99.9% 16S rRNA gene sequence similarities, 89.1–94.4% ANI and 39.0–55.5% dDDH values. Based upon the data obtained in the present study, three novel species, Lapidilactobacillus salsurivasis sp. nov., Secundilactobacillus muriivasis sp. nov. and Streptococcus parasalivarius sp. nov., are proposed and the type strains are 475-2T (= JCM 36613T = CCTCC AB 2023258T = LMG 33412T), 46-6BT (= JCM 36612T = CCTCC AB 2023259T = LMG 33411T) and 778-2T (= JCM 36614T = CCTCC AB 2023257T = LMG 33413T), respectively. [ABSTRACT FROM AUTHOR]

To provide the necessary nitrite for the Anaerobic Ammonium Oxidation (ANAMMOX) process, the effect of nitrite accumulation in the partial sulfide autotrophic denitrification (PSAD) process was investigated using an SBR reactor. The results revealed that the effectiveness of nitrate removal was unsatisfactory when the S/N ratio (mol/mol) fell below 0.6. The optimal conditions for nitrate removal and nitrite accumulation were achieved within the S/N ratio range of 0.7-0.8, resulting in an average Nitrate Removal Efficiency (NRE) of 95.84%±4.89% and a Nitrite Accumulation Rate (NAR) of 75.31%±6.61%, respectively. It was observed that the nitrate reduction rate was three times faster than that of nitrite reduction during a typical cycle test. Furthermore, batch tests were conducted to assess the influence of pH and temperature conditions. In the pH tests, it became evident that the PSAD process performed more effectively in alkaline environment. The highest levels of nitrate removal and nitrite accumulation were achieved at an initial pH of 8.5, resulting in a NRE of 98.30%±1.93% and a NAR of 85.83%±0.47%, respectively. In the temperature tests, the most favourable outcomes for nitrate removal and nitrite accumulation were observed at 22±1 ℃, with a NRE of 100.00% and a NAR of 81.03%±1.64%, respectively. Moreover, a comparative analysis of 16S rRNA sequencing results between the raw sludge and the sulfide-enriched culture sludge sample showed that Proteobacteria (49.51%) remained the dominant phylum, with Thiobacillus (24.72%), Prosthecobacter (2.55%), Brevundimonas (2.31%) and Ignavibacterium (2.04%) emerging as the dominant genera, assuming the good nitrogen performance of the system. [ABSTRACT FROM AUTHOR]

Although DNAzyme sensors have been widely developed for imaging metal ions, their application in specific subcellular compartments remains challenging due to low spatial controllability. Here we present a locally activatable, DNAzyme‐based sensing technology that enables subcellular compartment‐specific imaging of metal ions through ribosomal RNA (rRNA) regulated signal amplification. The system leverages a subcellularly encoded rRNA to locally activate DNAzyme‐based sensors, and further drives signal amplification via multiple turnover cleavage of molecular beacons, to significantly enhance sensitivity and spatial precision for metal‐ion imaging in specific organelles (e.g. mitochondria) or membraneless compartments (e.g. cytosol). Furthermore, we demonstrate that the system allows in situ monitoring of subcellular dynamics of mitochondrial Zn2+ during ischemia and the drug intervention. This study expands the DNAzyme toolbox for investigating the role of subcellular metal‐ion dynamics in disease processes. [ABSTRACT FROM AUTHOR]

Nucleic acid processing enzymes use a two‐Mg2+‐ion motif to promote the formation and cleavage of phosphodiester bonds. Yet, recent evidence demonstrates the presence of spatially conserved second‐shell cations surrounding the catalytic architecture of proteinaceous and RNA‐dependent enzymes. The RNase mitochondrial RNA processing (MRP) complex, which cleaves the ribosomal RNA (rRNA) precursor at the A3 cleavage site to yield mature 5′‐end of 5.8S rRNA, hosts in the catalytic core one atypically‐located Mg2+ ion, in addition to the ions forming the canonical catalytic motif. Here, we employ biased quantum classical molecular dynamics simulations of RNase MRP to discover that the third Mg2+ ion inhibits the catalytic process. Instead, its displacement in favour of a second‐shell monovalent K+ ion propels phosphodiester bond cleavage by enabling the formation of a specific hydrogen bonding network that mediates the essential proton transfer step. This study points to a direct involvement of a transient K+ ion in the catalytic cleavage of the phosphodiester bond and implicates cation trafficking as a general mechanism in nucleic acid processing enzymes and ribozymes. [ABSTRACT FROM AUTHOR]

Sauerkraut‐derived lactic acid bacterial (LAB) strains have gained attention due to their potential health benefits. This study focuses on evaluating seven Sauerkraut‐derived RAMULAB strains isolated from sauerkraut, aiming to identify promising candidates for modulating α‐glucosidase (AG) and α‐amylase (AM) enzymatic functions. RAMULAB strains with remarkable probiotic potential can contribute to the digestive health and manage conditions like diabetes. Identifying robust candidates from sauerkraut, a fermented food, holds promise for natural and cost‐effective probiotic sources. The RAMULAB strains underwent extensive characterization, including identification through 16S ribosomal RNA (rRNA) sequencing. Their tolerance to harsh conditions, adherence properties, antimicrobial activity, antioxidant potential, and inhibition of AG and AM were assessed. In silico analyses explored their molecular interactions, particularly with hydroxycitric acid, a potential antidiabetic compound. Among the RAMULAB strains, RAMULAB48 emerged as a standout candidate. It displayed exceptional resilience to acidic bile (≥97%), and simulated gastrointestinal conditions (≥95%), highlighting its suitability for probiotic applications. RAMULAB48 exhibited robust adherence properties, including cell‐surface hydrophobicity (80%), autoaggregation (42%), coaggregation with pathogens (≥33%), and adhesion to epithelial cells. Additionally, all seven isolates demonstrated gamma‐hemolysis and resistance to antibiotics (Kanamycin, Methicillin, and Vancomycin), while displaying strong antibacterial properties against foodborne pathogens. These RAMULAB strains also exhibited varying degrees of antioxidant activity, with RAMULAB48 displaying the highest potential (≥41%). In terms of antidiabetic activity, cell‐free supernatant (CS) obtained from RAMULAB48 expressed the highest inhibition levels, notably inhibiting yeast AG by an impressive 59.55% and AM being by a remarkable 67.42%. RAMULAB48 produced organic acids, including hydroxycitric acid (28.024 mg/mL), which showed promising antidiabetic properties through in silico analyses, indicating favorable interactions with the target enzymes. This study identifies Lacticaseibacillus paracasei RAMULAB48, a Sauerkraut‐derived RAMULAB strain, as a promising probiotic candidate with exceptional tolerance, adherence properties, antimicrobial activity, antioxidant potential, and antidiabetic effects. The presence of hydroxycitric acid further underscores its potential in managing diabetes. [ABSTRACT FROM AUTHOR]

ABSTRACT Aims Materials and Methods Results Conclusion To determine the relationship between microbiome dysbiosis indices and biofilm immunogenicity and their prognostic implications on periodontal treatment response.Thirty periodontally healthy controls and 30 periodontitis cases (stage III) were recruited. Cases received non‐surgical periodontal therapy (NSPT), and their treatment response at 6 months was evaluated using a treat‐to‐target endpoint (≤ 4 sites with probing depths ≥ 5 mm). Pooled subgingival biofilm samples were obtained from controls and cases. The V3–4 hypervariable region of the 16S rRNA gene was sequenced and two compositional indices (subgingival microbiome dysbiosis index, SMDI, and dysbiosis ratio, DR) were calculated. Nuclear factor kappa‐B (NF‐κB) activation elicited by biofilm samples in monocytic reporter cells was quantified to assess biofilm immunogenicity.SMDI, DR and biofilm immunogenicity were highly diagnostic for periodontitis (area under curves [AUC] > 0.90, p < 0.001). Among periodontitis cases, all three microbial parameters were significantly reduced after NSPT (p < 0.001). Cases achieving the treat‐to‐target endpoint had lower pre‐treatment SMDI and biofilm immunogenicity (p < 0.05) and different microbial recolonization patterns from poor responders. Both measures predicted treatment response (AUC of 0.767 and 0.835, respectively, p < 0.05).Subgingival biofilm dysbiosis quantified using SMDI and biofilm immunogenicity was diagnostic of periodontitis and predictive of NSPT outcomes. [ABSTRACT FROM AUTHOR]

Introduction: The One Health concept is a comprehensive understanding of the interaction between humans, animals, and the environment. The cohabitation of humans and pets positively affects their physical, mental, and social wellbeing. It is recognized as an essential factor from the One Health perspective. Furthermore, a healthy balance in the gut microbiome is essential for good health, and the changes in the gut microbiome associated with cohabitation between humans and pets could potentially affect various aspects of the health of both hosts. Therefore, elucidating the sharing of gut bacteria between humans and pets associated with cohabitation is important for understanding One Health. However, most studies have examined sharing at the taxonomic level, and it remains unclear whether the same bacteria are transferred between humans and pets, and whether they mutually influence each other. Methods: Here, microbiome analysis and shared 16S rRNA gene amplicon sequence variant (ASV) analysis were conducted before the start of cohabitation between humans and dogs, as well as at 2 weeks, 1 month, and 3 months after cohabitation. Results: 16S rRNA gene ASVs analysis indicated that gut microbes have been transferred between humans and dogs. The overall structure of the gut microbiota within human-dog pairs remained unchanged after 3 months of adaptation. However, 11ASVs were shared within human-dog pairs. Many shared ASVs were highly abundant within each host, and this high abundance may be considered a factor that influences bacterial transfer between hosts. Discussion: Our results provide important insights into the potential for the transfer of gut bacteria between humans and dogs. These findings are considered crucial for understanding the impact of human-dog cohabitation on various aspects of health. [ABSTRACT FROM AUTHOR]

Introduction: Plasmodium falciparum is the most damaging malaria pathogen and brings a heavy burden to global health. Host switching and morphological changes in P. falciparum are dependent on an effective gene expression regulatory system. C5 methylation of cytosines is a common RNA modification in eukaryotes, and the NSUN family are essential m5C modification executors. Currently, little is known about this family in Plasmodium spp. In this study, we focus on exploring the function of PfNSUN1 protein. Methods: An efficient CRISPR/Cas9 gene editing technique was applied to construct the PfNSUN1 knockdown strain. The knockdown efficiency was confirmed by growth curves and western blot experiments. The knockdown transcriptome data was acquired to find differentially expressed genes, and target genes of PfNSUN1 protein were identified by RNA immunoprecipitation and high-throughput sequencing experiments. Results: The efficiency of PfNSUN1 protein down-regulated was about 34%. RNA-seq data revealed that differentially expressed genes were mainly downregulated. And there were 224, 278, 556 genes that were down-regulated with more than 2-fold changes and p-adj<0.05 at ring, trophozoite and schizont stages, respectively. PfNSUN1 protein was significantly enriched on 154 target genes, including 28S ribosomal RNA and pfap2-g5 transcription factor. Discussion: PfNSUN1 is a crucial RNA post-transcriptional modification protein in P. falciparum. It plays a pivotal role in regulating gene expression and parasite growth by targeting 28S ribosomal RNA and pfap2-g5 transcription factor. [ABSTRACT FROM AUTHOR]

The low cultivability of environmental bacteria has been widely acknowledged, but most previous estimates focused on the proportion of cultivable cells rather than cultivable taxa. Here, we estimate the proportions of cultivable cells and cultivable taxa for two sample types (soil and activated sludge) using cell counting, 16S rRNA gene amplicon sequencing, metagenomics, and cultivation on agar plates under various conditions. We find that the proportion of cultivable taxa exceeds that of cultivable cells at the sample level. A large proportion of cultivable taxa are taxonomically novel but tend to be present at very low abundance on agar plates, forming microcolonies, and some of them cease to grow during subculture. Compared with uncultivable taxa (under the conditions used in our study), cultivatable taxa tend to display higher metabolic activity as inferred by measuring rRNA copies per cell. Finally, we use the generated taxonomic and genomic information as a guide to isolate a strain representing a yet-uncultured class within the Bacteroidota and to enhance the cultivable diversity of Burkholderiales from activated sludge. The low cultivability of most environmental bacteria is well known, but previous estimates focused on the proportion of cultivable cells. Here, the authors use various techniques to show, for soil and activated sludge samples, that the proportion of cultivable taxa exceeds that of cultivable cells, and identify genetic and physiological traits associated with cultivability. [ABSTRACT FROM AUTHOR]

Summary: Aberrant RNA modifications can lead to dysregulated gene expression and impeded growth in plants. Ribosomal RNA (rRNA) constitutes a substantial portion of total RNA, while the precise functions and molecular mechanisms underlying rRNA modifications in plants remain largely elusive.Here, we elucidated the exclusive occurrence of the canonical RNA modification N6‐methyladenosine (m6A) solely 18S rRNA, but not 25S rRNA. We identified a completely uncharacterized protein, ATMETTL5, as an Arabidopsis m6A methyltransferase responsible for installing m6A methylation at the 1771 site of the 18S rRNA. ATMETTL5 is ubiquitously expressed and localized in both nucleus and cytoplasm, mediating rRNA m6A methylation.Mechanistically, the loss of ATMETTL5‐mediated methylation results in attenuated translation. Furthermore, we uncovered the role of ATMETTL5‐mediated methylation in coordinating blue light‐mediated hypocotyl growth by regulating the translation of blue light‐related messenger RNAs (mRNAs), specifically HYH and PRR9.Our findings provide mechanistic insights into how rRNA modification regulates ribosome function in mRNA translation and the response to blue light, thereby advancing our understanding of the role of epigenetic modifications in precisely regulating mRNA translation in plants. [ABSTRACT FROM AUTHOR]

The continental bedrock contains groundwater-bearing fractures that are home to microbial populations that are vital in mediating the Earth's biogeochemical cycles. However, their diversity is poorly understood due to the difficulty of obtaining samples from this environment. Here, a groundwater-bearing fracture at 975 m depth was isolated by employing packers in order to characterize the microbial community via metagenomes combined with prokaryotic and eukaryotic marker genes (16S and 18S ribosomal RNA gene). Genome-resolved analyses revealed a community dominated by sulfate-reducing Bacillota, predominantly represented by Candidatus Desulforudis audaxviator and with Wood-Ljungdahl as the most prevalent pathway for inorganic carbon fixation. Moreover, the eukaryotic community had a considerable diversity and was comprised of mainly flatworms, chlorophytes, crustaceans, ochrophytes, and fungi. These findings support the important role of the Bacillota, with the sulfate reducer Candidatus Desulforudis audaxviator as its main representative, as primary producers in the often energy-limited groundwaters of the continental subsurface. Metagenomics combined with 16S and 18S ribosomal RNA sequencing on groundwater retrieved from a packer-isolated borehole provide insights into the microbial community at 975 m depth. [ABSTRACT FROM AUTHOR]

Background: Assembly of metagenomic samples can provide essential information about the mobility potential and taxonomic origin of antibiotic resistance genes (ARGs) and inform interventions to prevent further spread of resistant bacteria. However, similar to other conserved regions, such as ribosomal RNA genes and mobile genetic elements, almost identical ARGs typically occur in multiple genomic contexts across different species, representing a considerable challenge for the assembly process. Usually, this results in many fragmented contigs of unclear origin, complicating the risk assessment of ARG detections. To systematically investigate the impact of this issue on detection, quantification and contextualization of ARGs, we evaluated the performance of different assembly approaches, including genomic-, metagenomic- and transcriptomic-specialized assemblers. We quantified recovery and accuracy rates of each tool for ARGs both from in silico spiked metagenomic samples as well as real samples sequenced using both long- and short-read sequencing technologies. Results: The results revealed that none of the investigated tools can accurately capture genomic contexts present in samples of high complexity. The transcriptomic assembler Trinity showed a better performance in terms of reconstructing longer and fewer contigs matching unique genomic contexts, which can be beneficial for deciphering the taxonomic origin of ARGs. The currently commonly used metagenomic assembly tools metaSPAdes and MEGAHIT were able to identify the ARG repertoire but failed to fully recover the diversity of genomic contexts present in a sample. On top of that, in a complex scenario MEGAHIT produced very short contigs, which can lead to considerable underestimation of the resistome in a given sample. Conclusions: Our study shows that metaSPAdes and Trinity would be the preferable tools in terms of accuracy to recover correct genomic contexts around ARGs in metagenomic samples characterized by uneven coverages. Overall, the inability of assemblers to reconstruct long ARG-containing contigs has impacts on ARG quantification, suggesting that directly mapping reads to an ARG database should be performed as a complementary strategy to get accurate ARG abundance and diversity measures. [ABSTRACT FROM AUTHOR]

Background: Archaea and Bacteria are distinct domains of life that are adapted to a variety of ecological niches. Several genome-based methods have been developed for their accurate classification, yet many aspects of the specific genomic features that determine these differences are not fully understood. In this study, we used publicly available whole-genome sequences from bacteria ( N = 2546 ) and archaea ( N = 109 ). From these, a set of genomic features (nucleotide frequencies and proportions, coding sequences (CDS), non-coding, ribosomal and transfer RNA genes (ncRNA, rRNA, tRNA), Chargaff's, topological entropy and Shannon's entropy scores) was extracted and used as input data to develop machine learning models for the classification of archaea and bacteria. Results: The classification accuracy ranged from 0.993 (Random Forest) to 0.998 (Neural Networks). Over the four models, only 11 examples were misclassified, especially those belonging to the minority class (Archaea). From variable importance, tRNA topological and Shannon's entropy, nucleotide frequencies in tRNA, rRNA and ncRNA, CDS, tRNA and rRNA Chargaff's scores have emerged as the top discriminating factors. In particular, tRNA entropy (both topological and Shannon's) was the most important genomic feature for classification, pointing at the complex interactions between the genetic code, tRNAs and the translational machinery. Conclusions: tRNA, rRNA and ncRNA genes emerged as the key genomic elements that underpin the classification of archaea and bacteria. In particular, higher nucleotide diversity was found in tRNA from bacteria compared to archaea. The analysis of the few classification errors reflects the complex phylogenetic relationships between bacteria, archaea and eukaryotes. [ABSTRACT FROM AUTHOR]

Epinephelus bilobatus, Epinephelus maculatus and Epinephelus longispinis are three groupers that share common morphological characteristics and coloration patterns and have been morphologically confused and misidentified with each other for a long time. Complete mitochondrial genomes of the three groupers were determined and analyzed in this study. Mitogenomes of E. bilobatus, E. maculatus and E. longispinis were 17, 354 bp, 17, 066 bp and 17, 221 bp in size respectively and consisted of 13 protein-coding genes, two ribosomal RNA genes and one control region. However, different from most teleosts, which contain canonical 22 tRNAs, more numbers of tRNAs were identified in the three groupers with 27 tRNAs in E. bilobatus and E. longispinis and 25 tRNAs in E. maculatus. The increased number of tRNAs was due to the presence of tandemly duplicated tRNA-Asp genes that were located between tRNA-Ser and COII genes (six duplications in E. bilobatus and E. longispinis, four duplications in E. maculatus). Intact gene tandem duplication was an uncommon feature that was found in the typical teleost mitogenomes. The phylogenetic trees of the 32 groupers (genus Epinephelus) that were constructed based on 12 protein-coding genes revealed that Epinephelus species with tandemly duplicated tRNA-Asp genes were clustered into one monophyletic group, distinct from other Epinephelus species without any duplication features, which indicated that tandemly duplicated tRNA-Asp genes may be the particular linage-specific characteristics that evolve from a common ancestor and have the ability to distinguish them from other Epinephelus species. The results of the mitogenomes comparative analyses of the three groupers revealed the genetic distance of mitogenomes between each two species to be 0.062 (E. bilobatus vs E. maculatus), 0.091 (E. bilobatus vs E. longispinis) and 0.087 (E. maculatus vs E. longispinis). All values were far greater than the minimum value of 0.020 for species identification, which shows that they were three independent species at molecular level. Regarding the relationships between the three groupers, E. bilobatus was found to be more closely related to E. maculatus in comparison to E. longispinis. The results provide valuable molecular data for the species identification and phylogenetic analyses on E. bilobatus, E. maculatus and E. longispinis, and also provided a new insight into the tandem gene duplication features of Epinephelus mitogenomes. [ABSTRACT FROM AUTHOR]

Haloarchaeal cultures were isolated from solar salterns of Goa and Tamil Nadu and designated as BS2, BBK2 and E3. These isolates grew with a characteristic bright orange to pink pigmentation and were capable of growing in media containing upto 25% (w/vol) NaCl. Whole genome sequencing (WGS) of the three haloarchaeal strains BS2, BBK2 and E3 indicated an assembled genomic size of 4.1 Mb, 3.8 Mb and 4 Mb with G + C content of 61.8, 65.6 and 59.8% respectively. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the archaeal isolates belong to Haloarcula, Haloferax and Halogeometricum genera. Haloarcula rubripromontorii BS2 was predicted to have 4292 genes with 4242 CDS regions, 46 tRNAs, 6 rRNAs and 3 misc_RNAs. In case of Haloferaxlucentense BBK2, 3840 genes with 3780 CDS regions were detected along with 52 tRNAs, 5 rRNAs and 3 misc_RNAs. Halogeometricumborinquense E3 contained 4101 genes, 4043 CDS regions, 52 tRNAs, 4 rRNAs, and 2 misc_RNAs. The functional annotation and curation of the haloarchaeal genome, revealed C50 carotenoid biosynthetic genes like phytoene desaturase/carotenoid 3′ -4′ desaturase (crtI), lycopene elongase (ubiA/lyeJ) and carotenoid biosynthesis membrane protein (cruF) in the three isolates. Whereas crtD (C-3′,4′ desaturase), crtY (lycopene cyclase) and brp/blh (β-carotene dioxygenase) genes were identified only in BS2. [ABSTRACT FROM AUTHOR]

The genus Albatrellus is an important group of stipitate terrestrial fungi in the order Russulales. Some species in the genus form ectomycorrhizae, mostly with trees of Pinaceae; some are well-known edible mushrooms. However, its diversity and biogeography are unclear. Taxonomic and phylogenetic studies on Albatrellus were carried out by morphological examination, which included detailed observations of the fruiting body, spore shape and size, and other key features, together with potential hosts. These observations were then compared and analysed using multi-locus molecular phylogenetic analyses, including the internal transcribed spacer regions (ITS), the large subunit nuclear ribosomal RNA gene (nLSU), the translation elongation factor 1-α gene (tef1), the largest subunit of RNA polymerase II (rpb1), the second largest subunit of RNA polymerase II (rpb2), the small subunit mitochondrial rRNA gene (mtSSU), and the small subunit of the nuclear ribosomal RNA gene (nucSSU). The results demonstrated that the species of Albatrellus formed eight clades. Nine new species are described and illustrated, and two new combinations are proposed. A total of 38 species are accepted in Albatrellus worldwide. Of those species, 26, 7, and 8 species are distributed in Asia, Europe, and North America, respectively. The divergence time indicated that the maximum crown age of Albatrellus was approximately 70.5 million years ago, and East Asia and North America are the likely ancestral areas. Dispersal and differentiation to other continents occurred during the late Paleocene and Miocene. Three kinds of dispersal routes are proposed: East Asia and Europe, East Asia and North America, and Europe and North America. [ABSTRACT FROM AUTHOR]

Leaf surface microbial communities play an important role in forest ecosystems and are known to be affected by environmental and host conditions, including diseases impacting the host. Phytophthora agathidicida is a soil-borne pathogen that causes severe disease (kauri dieback) in one of New Zealand's endemic trees, Agathis australis (kauri). This research characterised the microbial communities of the A. australis phyllosphere (i.e. leaf surface) using modern molecular techniques and explored the effects of P. agathidicida on those communities. Fresh leaves were collected from trees where P. agathidicida was and was not detected in the soil and characterisation of the leaf surface microbial community was carried out via high-throughput amplicon sequencing of the internal transcribed spacer (ITS) and 16S ribosomal RNA regions. Nutrients in leaf leachates were also measured to identify other possible drivers of microbial diversity. The dominant phyllosphere microbial phylum was Proteobacteria followed by Acidobacteria. The phyllosphere microbial richness of A. agathis associated with P. agathidicida-infected soils was found to be generally lower than where the pathogen was not detected for both prokaryote (bacterial) and fungal phyla. Leaf leachate pH as well as boron and silicon had significant associations with bacterial and fungal community structure. These findings contribute to the development of a comprehensive understanding of A. australis leaf surface microbial communities and the effects of the soil pathogen P. agathidicida on those communities. [ABSTRACT FROM AUTHOR]

High levels of social connectivity among group-living animals have been hypothesized to benefit individuals by creating opportunities to rapidly reseed the microbiome and maintain stability against disruption. We tested this hypothesis by perturbing the microbiome of a wild population of Grant's gazelles with an antibiotic and asking whether microbiome recovery differs between individuals with high versus low levels of social connectivity. We found that after treatment, individuals with high social connectivity experienced a faster increase in microbiome richness than less socially connected individuals. Unexpectedly, the rapid increase in microbiome richness of highly connected individuals that received treatment led to their microbiomes becoming more distinct relative to the background population. Our results suggest that the microbiome of individuals with high social connectivity can be rapidly recolonized after a perturbation event, but this leads to a microbiome that is more distinct from, rather than more similar to the unperturbed state. This work provides new insight into the role of social interactions in shaping the microbiome. [ABSTRACT FROM AUTHOR]

Culture collections such as the Blue Biotechnology and Ecotoxicology Culture Collection (LEGE‐CC) hold approximately 1200 cyanobacterial strains and are critical community resources. However, many isolates in this and other collections have not been described with a polyphasic approach, and this limits further study. Here, we employed a polyphasic methodology that integrates 16S rRNA gene phylogenetic analyses, similarity (p‐distance), 16S‐23S ITS rRNA region secondary structures, morphological analyses, and habitat assessments to describe four novel cyanobacterial genera from the LEGE‐CC, Portugal. Pseudolimnococcus planktonicus gen. et sp. nov. (Chroococcales) is phylogenetically and morphologically related to Limnococcus. The 16S rRNA gene similarity between the types of both genera is only 93.1%. Morphologically, Pseudolimnococcus cells do not reach the original spherical shape before the next division or have aerotopes and firm mucilage, while Limnococcus cells reach the original shape, lack aerotopes, and have diffluent mucilage. Eucapsopsis lusitanus gen. et sp. nov. (Chroococcales) is morphologically similar to Eucapsis but differs from it by having aerotopes and diffluent envelope. Eucapsis lacks aerotopes and has firm mucilaginous envelopes, rarely diffluent. Both genera are phylogenetically very distant from each other and have only 90.68% 16S rRNA gene similarity. Pseudoacaryochloris arrabidensis gen. et sp. nov. (Acaryochloridales) differs from Acaryochloris by the lack of mucilaginous envelope, which is present in Acaryochloris. Both genera are phylogenetically distant and have only 94.1% 16S rRNA gene similarity. Moreover, Acaryochloris is marine (sponge symbiont), while Pseudoacaryochloris is from freshwater. Vasconcelosia minhoensis gen. et sp. nov. (Nodosilineales) is phylogenetically related to Cymatolege but has only 94.3% similarity with this genus. Morphologically both genera are distinct. Vasconcelosia has a Romeria‐like structure, while Cymatolege has a Phormidium‐like structure. In all cases the 16S‐23S ITS rRNA region secondary structures are in agreement with the other analyses. These novel genera expand the diversity of cyanobacteria in culture collections. [ABSTRACT FROM AUTHOR]

This investigation reports the polyphasic characterization of six cyanobacterial strains that were isolated from Basantgarh village of district Udhampur in the union territory of Jammu and Kashmir, India. Morphological examination of the isolated strains indicated that the strains are members of the genus Nostoc or its morphotypes. Phylogenetic analyses using the 16S rRNA gene showed that five strains clustered in the Nostoc sensu stricto clade, whereas one strain clustered in the Desmonostoc clade. Further, comparative studies with their phylogenetically related taxa, based on morphology, folded secondary structures, phylogeny of the ITS rRNA region, and the percent genetic homology of 16S rRNA gene and ITS rRNA region clearly established the strains as novel taxa belonging to the genera Nostoc and Desmonostoc. Also, two strains 21A‐PS and 2JNA‐PS emerged as conspecific to each other, representing the same species of Nostoc. Hence, in accordance with the International code of Nomenclature for algae, fungi, and plants, this study describes Nostoc jammuense, Nostoc globosum, Nostoc breve, and Nostoc coriaceum, as novel species of the genus Nostoc, while Desmonostoc raii is described as a novel species of the genus Desmonostoc. This study adds novel species of Nostoc from Indian habitats and reinforces the need to explore the Nostoc sensu stricto clade for more novel taxa. [ABSTRACT FROM AUTHOR]

The rapid expansion of whole genome sequencing in bacterial taxonomy has revealed deep evolutionary relationships and speciation signals, but assembly methods often miss true nucleotide diversity in the ribosomal operons. Though it lacks sufficient phylogenetic signal at the species level, the 16S ribosomal RNA gene is still much used in bacterial taxonomy. In cyanobacterial taxonomy, comparisons of 16S–23S Internal Transcribed Spacer (ITS) regions are used to bridge this information gap. Although ITS rRNA region analyses are routinely being used to identify species, researchers often do not identify orthologous operons, which leads to improper comparisons. No method for delineating orthologous operon copies from paralogous ones has been established. A new method for recognizing orthologous ribosomal operons by quantifying the conserved paired nucleotides in a helical domain of the ITS, has been developed. The D1′ Index quantifies differences in the ratio of pyrimidines to purines in paired nucleotide sequences of this helix. Comparing 111 operon sequences from 89 strains of Brasilonema, four orthologous operon types were identified. Plotting D1′ Index values against the length of helices produced clear separation of orthologs. Most orthologous operons in this study were observed both with and without tRNA genes present. We hypothesize that genomic rearrangement, not gene duplication, is responsible for the variation among orthologs. This new method will allow cyanobacterial taxonomists to utilize ITS rRNA region data more correctly, preventing erroneous taxonomic hypotheses. Moreover, this work could assist genomicists in identifying and preserving evident sequence variability in ribosomal operons, which is an important proxy for evolution in prokaryotes. [ABSTRACT FROM AUTHOR]

Two new species of Dulcicalothrix, D. adhikaryi sp. nov. and D. iyengarii sp. nov., were discovered in India and are characterized and described in accordance with the rules of the International Code of Nomenclature for algae, fungi, and plants (ICN). As a result of phylogenetic analysis, Calothrix elsteri is reassigned to Brunnivagina gen. nov. During comparison with all Dulcicalothrix for which sequence data were available, we observed that the genus has six ribosomal operons in three orthologous types. Each of the three orthologs could be identified based upon indels occurring in the D1–D1′ helix sequence in the ITS rRNA region between the 16S and 23S rRNA genes, and in these three types, there were operons containing ITS rRNA regions with and without tRNA genes. Examination of complete genomes in Dulcicalothrix revealed that, at least in the three strains for which complete genomes are available, there are five ribosomal operons, two with tRNA genes and three with no tRNA genes in the ITS rRNA region. Internal transcribed spacer rRNA regions have been consistently used to differentiate species, both on the basis of secondary structure and percent dissimilarity. Our findings call into question the use of ITS rRNA regions to differentiate species in the absence of efforts to obtain multiple operons of the ITS rRNA region through cloning or targeted PCR amplicons. The ITS rRNA region data for Dulcicalothrix is woefully incomplete, but we provide herein a means for dealing with incomplete data using the polyphasic approach to analyze diverse molecular character sets. Caution is urged in using ITS rRNA data, but a way forward through the complexity is also proposed. [ABSTRACT FROM AUTHOR]

Sugarcane thrips, Fulmekiola serrata (Kobus) (Thysanoptera: Thripidae), is a common foliar pest that infests sugarcane and is found throughout tropical and subtropical countries. In this study, we obtained and analyzed the complete mitochondrial genome of F. serrata for the first time and explored the phylogenetic relationships of the higher-order elements of Thysanoptera members at the mitochondrial level. The complete mitochondrial genome of F. serrata is 16,596 bp in length and includes 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and 1 noncoding control region. A+T accounted for 75% of the total bases in the mitochondrial genome of F. serrata, revealing an obvious AT bias. Among the 13 PCGs, except for nad5, which had a start codon of TTG, the remaining genes had ATNs typical of insects (ATA, ATT, ATC, and ATG); nad1, nad2, nad3, and atp8 had incomplete termination codons of TA or T. The remaining nine PCGs were complete with the termination codon TAA. Of the 22 tRNA secondary structures, all were typical cloverleaf secondary structures except for trnS1, which was missing the DHU arm. Compared with the hypothetical ancestral gene arrangement of arthropods, F. serrata presented extensive gene rearrangement, with 23 translocated genes, 8 inverted genes, and 5 shuffled genes. Both maximum likelihood (ML) and Bayesian inference (BI) phylogenetic trees resulted in similar topologies: ((Thripidae + (Stenurothripidae + Aeolothripidae)) + Phlaeothripidae), with Thripidae, Aeolothripidae and Phlaeothripidae being monophyletic groups, whereas F. serrata is closely related to Thrips palmi, and the two are sister groups. [ABSTRACT FROM AUTHOR]

SUMMARY: The diatom genus Druehlago was established to differentiate the type species from Craspedostauros and Achnanthes, on the basis of unique heteropolar, cuneate frustules and numerous lenticular plastids. The phylogenetic placement of Druehlago has, until now, relied solely on morphological evidence, suggesting a close relationship with the genus Craspedostauros. In the present study, we discovered a population of Druehlago cf. cuneata along the coast of Japan and established a cultured strain. Molecular phylogenetic analysis based on rbcL, psbC and 18S rRNA genes was conducted to explore the phylogenetic position and classification of Druehlago. Our results revealed that D. cf. cuneata belongs to the Craspedostauros clade, but with weak statistical support, which is, in turn, sister to Achnanthes. Given the lack of support for various nodes within the Craspedostauros clade, constrained trees were constructed based on several hypotheses regarding the phylogenetic position of Druehlago. The hypothesis inferring monophyly of Druehlago and Achnanthes was statistically rejected, which highlights the close relationship between Druehlago and Craspedostauros. However, our topology tests provided no further resolution regarding the phylogenetic position of Druehlago within or outside Craspedostauros. Furthermore, the treatment of the specimens is discussed through a morphological comparison with the type of material. [ABSTRACT FROM AUTHOR]

The use of short‐read metabarcoding for classifying microeukaryotes is challenged by the lack of comprehensive 18S rRNA reference databases. While recent advances in high‐throughput long‐read sequencing provide the potential to greatly increase the phylogenetic coverage of these databases, the performance of different sequencing technologies and subsequent bioinformatics processing remain to be evaluated, primarily because of the absence of well‐defined eukaryotic mock communities. To address this challenge, we created a eukaryotic rRNA operon clone‐library and turned it into a precisely defined synthetic eukaryotic mock community. This mock community was then used to evaluate the performance of three long‐read sequencing strategies (PacBio circular consensus sequencing and two Nanopore approaches using unique molecular identifiers) and three tools for resolving amplicons sequence variants (ASVs) (USEARCH, VSEARCH, and DADA2). We investigated the sensitivity of the sequencing techniques based on the number of detected mock taxa, and the accuracy of the different ASV‐calling tools with a specific focus on the presence of chimera among the final rRNA operon ASVs. Based on our findings, we provide recommendations and best practice protocols for how to cost‐effectively obtain essentially error‐free rRNA operons in high‐throughput. An agricultural soil sample was used to demonstrate that the sequencing and bioinformatic results from the mock community also translates to highly diverse natural samples, which enables us to identify previously undescribed microeukaryotic lineages. [ABSTRACT FROM AUTHOR]

Environmental variation can shape the gut microbiome, but broad/large‐scale data on among and within‐population heterogeneity in the gut microbiome and the associated environmental factors of wild populations is lacking. Furthermore, previous studies have limited taxonomical coverage, and knowledge about wild avian gut microbiomes is still scarce.We investigated large‐scale environmental variation in the gut microbiome of wild adult great tits across the species' European distribution range. We collected fecal samples to represent the gut microbiome and used the 16S rRNA gene sequencing to characterize the bacterial gut microbiome.Our results show that gut microbiome diversity is higher during winter and that there are compositional differences between winter and summer gut microbiomes. During winter, individuals inhabiting mixed forest habitat show higher gut microbiome diversity, whereas there was no similar association during summer. Also, temperature was found to be a small contributor to compositional differences in the gut microbiome. We did not find significant differences in the gut microbiome among populations, nor any association between latitude, rainfall and the gut microbiome.The results suggest that there is a seasonal change in wild avian gut microbiomes, but that there are still many unknown factors that shape the gut microbiome of wild bird populations. [ABSTRACT FROM AUTHOR]

Background Objective Methods Results Conclusion More than 50% of patients with hand eczema (HE) are colonized with Staphylococcus aureus. Comprehensive knowledge of the skin microbiome and its changes in patients with HE may provide insights into future potential therapeutical targets.To describe the skin microbiome in patients with moderate‐to‐severe chronic HE and assess its changes following treatment with topical corticosteroids (TCS).Bacterial samples were collected from lesional and nonlesional skin before and after 2 weeks of TCS treatment using ESwabs and analysed by 16S rRNA and tuf gene sequencing. Clinically, the disease severity was assessed by the Hand Eczema Severity Index (HECSI).A cohort of 31 patients with HE were included and followed up. Compared to nonlesional skin, lesional skin differed in overall bacterial community composition (p = 0.02), displayed higher relative abundance of Staphylococcus, in particular S. aureus (p = 0.01) and lower abundance of Micrococcus (p = 0.02). As disease severity improved with treatment, these microbial characteristics on lesional skin shifted towards that of nonlesional skin on the hands.The bacterial skin microbiome was altered in lesions of HE and partly driven by S. aureus colonization, however, shifted towards nonlesional skin following treatment. Our results emphasize the future possibilities for anti‐S. aureus treatment strategies. [ABSTRACT FROM AUTHOR]

Xylophilus ampelinus is a xylematic bacterium causing bacterial blight of grapevine, a disease regarded as a potential threat for viticulture in several countries. Currently, PCR detection is pivotal in diagnostic protocols due to the bacterium's infrequent occurrence in the field and the technical advantages of PCR. Recent metagenomic studies have unveiled diversity in its taxonomic domain, unknown when the most widely used assays for the detection of X. ampelinus infections were developed. In particular, PCR assays relying on highly conserved sequence regions, such as those surrounding ribosomal RNA genes, may be substituted with more specific PCR assays. In this study, we first investigated the diversity of detectable grapevine endophytes related to but different from X. ampelinus and delineated the genotaxonomic boundaries of the species in relation to the known (meta)genomes of closely related bacteria. Then, by exploiting the wealth of genomes now available for bacteria classified in the Burkholderiales, we devised several sets of primers targeting only X. ampelinus and its closest relatives. These primers were employed to (i) genotaxonomically circumscribe the grapevine endophyte species related to but distinguishable from X. ampelinus and (ii) develop a robust multiplex PCR assay expected to be specific for the species X. ampelinus based on in vitro and in silico evidence. The adoption of the multiplex PCR assay presented here is expected to reduce the risk of false positives in the diagnosis of bacterial blight of grapevine. [ABSTRACT FROM AUTHOR]

Trichomonas gallinae is a widespread protozoan parasite that primarily affects birds, causing a disease known as avian trichomonosis. The present study aimed to investigate the prevalence and genetic diversity of T. gallinae, a parasite causing avian trichomoniasis in feral pigeons, budgerigars, and finches in Tehran, Iran. The 5.8S ribosomal RNA locus, along with the internal transcribed spacer 2 (ITS2) region, has been extensively utilized for genotype identification and for determining inter- and intra-specific diversity. More recently, the Fe-hydrogenase (Fe-Hyd) gene has been suggested as an additional genetic marker to enhance the accuracy of strain subtyping discrimination. In the present study, a total of 12% (12/100) birds examined were infected with T. gallinae using microscopy and PCR methods. Infection was found in seven of 30 (23.3%) feral pigeons, three of 40 (7.5%) budgerigars, and two of 30 (6.66%) finches. Analysis of the ITS2 region of T. gallinae isolates revealed two highly similar sequences. The first sequence (GenBank: OQ689964-OQ689970) was found in five feral pigeons and two budgerigars, whereas the second sequence (GenBank: OQ689971-OQ689975) was identified in two feral pigeons, one budgerigar, and two finches. Phylogenetic analysis confirmed the presence of two distinct clusters (cluster I and cluster II) within the trichomonads based on the ITS2 region. However, further analysis using Fe-Hyd revealed greater diversity, with three subtypes identified (A1, A2, and C1). One isolate identified in the present study (GenBank accession number: OQ694508.1) belonged to subtype A1. Combining ITS2 and Fe-Hyd markers holds promise for a more comprehensive understanding of the population structure of T. gallinae and the potential role of ITS2 in host adaptation. [ABSTRACT FROM AUTHOR]

Pirsoniales is a stramenopile order composed of marine parasitoids of diatoms with unique life cycle. Until recently, a single genus, Pirsonia, uniting six species, was known. The recent identification of new free‐living eukaryotrophic Pirsoniales Pirsonia chemainus, Feodosia pseudopoda, and Koktebelia satura changed our understanding of this group as exclusively parasitic. However, their cell ultrastructure and feeding preferences were not fully studied due to the death of the cultures. In this study, we re‐isolated some of these Pirsoniales and established six new strains exhibiting predatory behavior, including a first freshwater representative. This allowed us to describe five new genera and species, as well as to emend the diagnosis of the order Pirsoniales. The 18S rRNA gene phylogenetic analysis revealed the position of new strains within Pirsoniales and their relationships with parasitoid relatives and environmental sequence lineages. Feeding experiments on novel Pirsoniales strains using diverse algal prey showed that they were not able to form trophosomes and auxosomes. The ability of cell aggregation in Pirsoniales was observed for the first time. One of the studied strains contained intracellular gammaproteobacteria distantly related to Coxiella. Ultrastructural analyses revealed a more complex cytoskeleton structure in Pirsoniales than previously thought and supported the monophyly of Bigyromonadea and Pseudofungi. [ABSTRACT FROM AUTHOR]

Background: Optimal management of intracranial infections relies on microbiological diagnosis and antimicrobial choice, but conventional culture-based testing is limited by pathogen viability and pre-sampling antimicrobial exposure. Broad-range 16S rRNA gene sequencing has been reported in the management of culture-negative infections but its utility in intracranial infection is not well-described. We studied the efficacy of 16S rRNA gene sequencing to inform microbiological diagnosis and antimicrobial choice in intracranial infections. Methods: This was a retrospective study of all intraoperative neurosurgical specimens sent for 16S rRNA gene sequencing over an 8-year period at a regional neurosurgical centre in the UK. Specimen selection was performed using multidisciplinary approach, combining neurosurgical and infection specialist discussion. Results: Twenty-five intraoperative specimens taken during neurosurgery from 24 patients were included in the study period. The most common reason for referral was pre-sampling antimicrobial exposure (68%). Bacterial rDNA was detected in 60% of specimens. 16S rRNA gene sequencing contributed to microbiological diagnosis in 15 patients and informed antimicrobial management in 10 of 24 patients with intracranial infection. These included targeted antibiotics after detection of a clinically-significant pathogen that had not been identified through other microbiological testing (3 cases), detection of commensal organisms in neurosurgical infection which justified continued broad cover (2 cases) and negative results from intracranial lesions with low clinical suspicion of bacterial infection which justified avoidance or cessation of antibiotics (5 cases). Conclusion: Overall, 16S rRNA gene sequencing represented an incremental improvement in diagnostic testing and was most appropriately used to complement, rather than replace, conventional culture-based testing for intracranial infection. [ABSTRACT FROM AUTHOR]

In this study, we aimed to develop a species-level phylogeny for the Nannospalax genus, identify cryptic species that are difficult to differentiate using standard methods, and further evaluate the relationships across chromosomal forms of several species. 16S rRNA gene sequences from 81 Turkish regions were evaluated and statistical analyzes were conducted. Results are as follows; (i) Nannospalax cilicicus was found to be monophyletic and sister in relation to Nannospalax xanthodon; (ii) We suggested for the first time that the Central-Anatolian populations should be classified under the species name Nannospalax cilicicus (stat. n.); (iii) the unidentified 2n = 52 cytotypes from Bolu and Nannospalax leucodon cytotypes were reciprocally monophyletic, these data support the notion that the 2n = 52 cytotypes from Bolu belong to an unidentified taxon; (iv) study also offered evidence for the monophyly of N. tuncelicus for the first time; (v) Nannospalax xanthodon (2n = 36, 38, and 40) and Nannospalax nehringi composed several species-specific clades, which form polytomy structure, so relationships between these species are still unclear. [ABSTRACT FROM AUTHOR]

This study aimed to characterize the taxonomic composition of intraradicular multispecies biofilms (IMB) formed in situ in a model to reproduce clinical conditions. Twelve palatal roots of maxillary molars had its canals prepared. Two roots were randomly selected to sterility control. Ten intraoral prosthetic appliances with lateral slots were fabricated. The roots were positioned in the slots with the canal access open to the oral cavity. Eight volunteers wore the appliance for 21 days, and two wore it at two different time points. One root from each appliance was removed and stored at −20°C until DNA extraction and sequencing (n = 10). Biofilm was analyzed using next‐generation sequencing and bioinformatics. The V4 hyper‐variable region of the 16SrRNA gene was amplified and sequenced. For data analyses, the mothur pipeline was used for 16SrRNA processing, and subsequent analyses of the sequence dataset were performed in R using the Microbiome Analyst R package. The taxonomy‐based analysis of bacterial communities identified 562 operational taxonomic units (OTUs), which belonged to 93 genera, 44 families, and 8 phyla. Bacterial colonization was different for each biofilm, and samples did not have the same group of bacteria. Alpha and beta diversity analysis revealed some general patterns of sample clustering. A core microbiome of prevalent OTUs and genera was identified. IMBs were heterogeneous when analyzed individually, but some diversity patterns were found after sample clustering. The experimental model seemed to reproduce the actual biofilm composition in endodontic infections, which suggests that it may be used to evaluate disinfection protocols. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to identify, discover and explore the characteristics of the mtDNA genomes of Cemani chicken (Gallus gallus). Methods: This study used gDNA of Cemani chicken isolated from liver tissue. mtDNA sequencing was performed using WGS mtDNA analysis with nanopore technology by Oxford Nanopore Technologies GridION. Bioinformatics and data analysis were then performed. Results: This study showed that the length of the mtDNA genome is 16,789 bp, consisting of two ribosomal RNA (12S rRNA, 16S rRNA), 22 transfer RNA genes (trnR, trnG, trnK, trnD, trnS, trnY, trnC, trnN, trnA, trnW, trnM, trnQ, trnl, trnL, trnV, trnF, trnP, trnT, trnE, trnL, trnS, trnH), 13 protein-coding genes (PCGs) (ND4l, ND3, COX3, ATP6, ATP8, COX2, COX1, ND2, ND1, CYTB, ND6, ND5, ND4), and a noncoding control region (Dloop). Furthermore, analysis showed there were polymorphic sites and amino acid alterations when mtDNA Cemani chicken was aligned with references from GenBank. Conclusion: Site (988T>*) in Dloop genes and (328A>G) in ND3 genes which alter glycine to stop codon, were specific markers found only in Cemani chicken. [ABSTRACT FROM AUTHOR]

6-Hydroxynicotinic acid emerged as a pivotal intermediate for fine chemicals. The current study aims to screen novel nicotinate dehydrogenase-producing strains. Based on the high-throughput UV coloration method, a novel nicotinate dehydrogenase-producing strain named Bacillus paramycoides was first and successfully screened from soil and gram staining as 16S rRNA gene sequencing was conducted to further confirm its accuracy. The fermentation medium formula is determined as seignette salt (5 g/L), tryptone (10 g/L), K2HPO4 (2 g/L), and nicotinic acid (4 g/L) after a single factor and orthogonal test. The activity of nicotinate dehydrogenase produced by B. paramycoides after optimization reached 1.23 U/mL, which was the highest ever reported. In addition, the enzyme characterization results revealed that the optimum reaction temperature and pH were 40 °C and 7.0, respectively. Furthermore, B. paramycoides nicotinate dehydrogenase exhibited good thermostability with more than 50% of the highest enzyme activity retained at 50 °C after 8 h incubation, which was better than ever reported. The pH stability results suggested that nicotinate dehydrogenase possessed a narrow pH ranging from 6.0 to 8.0. In addition, shaker speed demonstrated a positive relation with enzyme activity since shaker speed could affect mass transfer and dissolved oxygen concentration. Finally, it could completely transform nicotinic acid to 6-HNA within 3 h when the substrate loading is 15 g/L. In conclusion, these results indicated that B. paramycoides nicotinate dehydrogenase could serve as a potential candidate for bioproduction of 6-HNA. [ABSTRACT FROM AUTHOR]

Mitoribosome biogenesis is a complex process involving RNA elements encoded in the mitochondrial genome and mitoribosomal proteins typically encoded in the nuclear genome. This process is orchestrated by extra‐ribosomal proteins, nucleus‐encoded assembly factors, which play roles across all assembly stages to coordinate ribosomal RNA processing and maturation with the sequential association of ribosomal proteins. Both biochemical studies and recent cryo‐EM structures of mammalian mitoribosomes have provided insights into their assembly process. In this article, we will briefly outline the current understanding of mammalian mitoribosome biogenesis pathways and the factors involved. Special attention is devoted to the recent identification of iron–sulfur clusters as structural components of the mitoribosome and a small subunit assembly factor, the existence of redox‐sensitive cysteines in mitoribosome proteins and assembly factors, and the role they may play as redox sensor units to regulate mitochondrial translation under stress. [ABSTRACT FROM AUTHOR]

Background: Mosquitoes (Culicidae), as disease vectors, represent a risk for human health worldwide. Repeated introductions of alien mosquito species and the spread of invasive species have been recorded in different countries. Traditionally, identification of mosquitoes relies on morphological observation. However, morphology-based identification is associated with a number of potential disadvantages, such as the high level of specialisation of the operator and its limited applicability to damaged samples. In these cases, species identification is achieved through molecular methods based on DNA amplification. Molecular-based taxonomy has also enabled the development of techniques for the study of environmental DNA (eDNA). Previous studies indicated the 16S mitochondrial ribosomal RNA (rRNA) gene as a promising target for this application; however, 16S rRNA sequences are available for only a limited number of mosquito species. In addition, although primers for the 16S rRNA gene were designed years ago, they are based on limited numbers of mosquito sequences. Thus, the aims of this study were to: (i) design pan-mosquito 16S rRNA gene primers; (ii) using these primers, generate a 16S rRNA gene mosquito reference library (with a focus on mosquitoes present in Italy); and (iii) compare the discriminatory power of the 16S rRNA gene with two widely used molecular markers, cytochrome c oxidase subunit 1 mitochondrial gene (COI) and internal transcribed spacer 2 (ITS2). Methods: A total of six mosquito genera (28 mosquito species) were included in this study: Aedes (n = 16 species), Anopheles (5 species), Coquillettidia (1 species), Culex (3 species), Culiseta (2 species) and Uranotaenia (1 species). DNA was extracted from the whole mosquito body, and more than one specimen for each species was included in the analysis. Sanger sequencing was used to generate DNA sequences that were then analysed through the Barcode of Life Data Systems (BOLD). Phylogenetic analyses were also performed. Results: Novel 16S rDNA gene, COI and ITS2 sequences were generated. The 16S rRNA gene was shown to possess sufficient informativeness for the identification of mosquito species, with a discriminatory power equivalent to that of COI. Conclusions: This study contributes to the generation of DNA barcode libraries, focussed on Italian mosquitoes, with a significant increase in the number of 16S rRNA gene sequences. We hope that these novel sequences will provide a resource for studies on the biodiversity, monitoring and metabarcoding of mosquitoes, including eDNA-based approaches. [ABSTRACT FROM AUTHOR]

Background: Clustering of sequences into operational taxonomic units (OTUs) and denoising methods are a mainstream stopgap to taxonomically classifying large numbers of 16S rRNA gene sequences. Environment-specific reference databases generally yield optimal taxonomic assignment. Results: We developed SpeciateIT, a novel taxonomic classification tool which rapidly and accurately classifies individual amplicon sequences (https://github.com/Ravel-Laboratory/speciateIT). We also present vSpeciateDB, a custom reference database for the taxonomic classification of 16S rRNA gene amplicon sequences from vaginal microbiota. We show that SpeciateIT requires minimal computational resources relative to other algorithms and, when combined with vSpeciateDB, affords accurate species level classification in an environment-specific manner. Conclusions: Herein, two resources with new and practical importance are described. The novel classification algorithm, SpeciateIT, is based on 7th order Markov chain models and allows for fast and accurate per-sequence taxonomic assignments (as little as 10 min for 107 sequences). vSpeciateDB, a meticulously tailored reference database, stands as a vital and pragmatic contribution. Its significance lies in the superiority of this environment-specific database to provide more species-resolution over its universal counterparts. [ABSTRACT FROM AUTHOR]

The Diphyllatea (CRuMs) are heterotrophic protists currently divided into three distinct clades (Diphy I–III). Diphy I are biflagellates in the genus Diphylleia, whereas Diphy II and III represent cryptic clades comprising Collodictyon‐type quadriflagellates that were recently distinguished based on rRNA gene phylogenies. Here, we isolated Diphyllatea from freshwater crater lakes on two South Pacific islands and generated high‐quality transcriptomes from species representing each clade, including the first transcriptomic data from Diphy III. Phylogenomic analyses support the separation of Diphy II and III, while transcriptome completeness highlights the utility of these data for future studies. Lastly, we discuss the biogeography and ecology of Diphyllatea on these remote islands. [ABSTRACT FROM AUTHOR]

China has a complex and diverse forest ecological environment, which breeds abundant forest macrofungi, including some edible, medicinal, and poisonous species. During the investigations of macrofungi in the Saihanba National Nature Reserve, North China, we collected abundant specimens of Agaricales and Polyporales within the Agaricomycetes. Based on the morphological characters and molecular evidence of DNA sequences including the internal transcribed spacer (ITS) regions, the large subunit of nuclear ribosomal RNA gene (nLSU), the small subunit of mitochondrial rRNA gene (mtSSU), the small subunit of nuclear ribosomal RNA gene (nuSSU), the largest subunit of RNA polymerase II (RPB1), the second largest subunit of RNA polymerase II gene (RPB2), the β-tubulin gene (TUB), and the translation elongation factor 1-α gene (TEF1), this study identifies ten species of Agaricales and Polyporales new to science, viz. Cyanosporus subpopuli, Gelatinofungus betulina, Lycoperdon pseudoperlatum, Macrocystidia hebeiensis, Mycena subbrunnea, M. subpura, M. variispora, M. violocea-ardesiaca, Picipes griseus, and Pleuroflammula hebeiensis. Detailed morphological descriptions, fruiting bodies, and microscopic structure diagrams of these ten novel species are provided. [ABSTRACT FROM AUTHOR]

A 6-year-old male neutered boxer mix canine was presented for a one-month history of dyschezia, hematochezia, and constipation. Colonoscopy and endoscopic biopsies revealed non-specific lymphoplasmacytic, eosinophilic colitis. Despite pursuing various therapies over a 3.5-month clinical course (including hypoallergenic diet, antibiotics, prokinetics, laxatives, and antiinflammatory glucocorticoids), the patient's condition did not improve. Two and a half months after initial presentation, the patient developed circumferential proctitis with multiple draining tracts and obstipation. Humane euthanasia and postmortem examination were elected. Gross and histological findings revealed locally extensive pyogranulomatous coloproctitis with many intralesional PASpositive, GMS-negative 30-40 µm in diameter, hyaline, pauciseptate, irregularly branching fungal hyphae, hyphal bodies or chlamydospores and 25-45 µm in diameter thick-walled zygospores. Fungal culture of fluid from the draining tracts was performed, and DNA sequence analysis of the ITS and partial LSU of the nuclear ribosomal RNA genes were used to identify and confirm a novel species, Basidiobolus arizonensis. Basidiobolus spp. are saprobes in the order Basidiobolales and most commonly cause granulomatous infections of the skin, respiratory tract, and gastrointestinal tract in veterinary species and humans. To the authors' knowledge, this is the first report of novel Basidiobolus arizonensis causing localized coloproctitis in a dog. [ABSTRACT FROM AUTHOR]

A novel species of Mucor was identified as the causal agent of a brown rot of Prunus domestica (European plum), widely grown in the south of Xinjiang, China. This disease first appears as red spots after the onset of the fruits. With favorable environmental conditions, fruit with infected spots turn brown, sag, expand, wrinkle, and harden, resulting in fruit falling. Fungal species were isolated from infected fruits. A phylogenetic analysis based on internal transcribed spacer (ITS) regions and the large subunit (LSU) of the nuclear ribosomal RNA (rRNA) gene regions strongly supported that these isolates made a distinct evolutionary lineage in Mucor (Mucoromycetes, Mucoraceae) that represents a new taxonomic species, herein named as Mucor xinjiangensis. Microscopic characters confirmed that these strains were morphologically distinct from known Mucor species. The pathogenicity of M. xinjiangensis was confirmed by attaching an agar disk containing mycelium on fruits and re-isolation of the pathogen from symptomatic tissues. Later, fourteen fungicides were selected to determine the inhibitory effect on the pathogen. Further, results showed that difenoconazole had the best effect on the pathogen and the strongest toxicity with the smallest half maximal effective concentration (EC50) value, followed by a compound fungicide composed of difenoconazole with azoxystrobin, mancozeb, prochloraz with iprodione, pyraclostrobin with tebuconazole, and trifloxystrobin with tebuconazole and ethhylicin. Present study provides the basis for the prevention and control of the novel plum disease and its pathogen. [ABSTRACT FROM AUTHOR]

Introduction: To investigate the presence of dysbiosis in patients with naive bladder cancer. Methods: Twelve male patients with non-invasive bladder cancer and twelve age-matched healthy males had midstream urine and tissue samples taken. A history of endourological interventions was determined as an exclusion criterion, ensuring that the study was designed solely with naïve participants. The bacterial 16s ribosomal RNA V3-V4 regions were used to examine urine and tissue samples. We compared the microbiota composition of the bladder cancer and control groups. Results: Escherichia Shigella (p < 0.001), Staphylococcus (p < 0.001), Delftia (p < 0.001), Acinetobacter (p < 0.001), Corynebacterium (p < 0.001), and Enhydrobacter (p < 0.001) were abundant in bladder cancer tissue samples. Escherichia Shigella (p < 0.001), Ureaplasma (p < 0.001), Lactobacillus (p = 0.005), Stenotrophomonas (p < 0.001), Streptococcus (p < 0.001), Corynebacterium (p < 0.001), and Prevotella (p = 0.039) were abundant in bladder cancer urine samples. Midstream urine has a sensitivity of 83% for detecting dysbiotic bacteria in cancer tissue. Conclusions: Our research is the first microbiota study of bladder cancer done with naive patients who have never had an endourological intervention. Escherichia Shigella, Staphylococcus, Acinetobacter, Enhydrobacter, Delftia, Corynebacterium, and Pseudomonas were detected as dysbiotic bacteria in bladder cancer. The sensitivity of the midstream urine sample in detecting dysbiosis in tissue is 83%. [ABSTRACT FROM AUTHOR]

Background: Cryptosporidium spp. is a ubiquitous, globally distributed intestinal protozoan infecting humans and at least 260 animal hosts. Due to close human contact with pet dogs and identification of zoonotic Cryptosporidium species and subtypes in these animals, dog health is not only a veterinarian issue but also a public health issue. This study aimed to understand occurrence and genetic characterization at both genotype and subtype levels in pet dogs in Yunnan Province, China. Results: A total of 589 fresh fecal specimens were collected from adult pet dogs in the rural areas of eight cities/autonomous prefectures of Yunnan Province, China. 16 fecal specimens were positive for Cryptosporidium spp. by polymerase chain reaction (PCR) amplification and sequence analysis of the small subunit ribosomal RNA (SSU rRNA) gene, with an average occurrence rate of 2.7% (16/589) being observed. Three zoonotic Cryptosporidium species were identified: C. parvum (n = 7), C. suis (n = 5) and C. canis (n = 4). At the 60-kDa glycoprotein (gp60) locus, only three C. parvum and two C. canis specimens were successfully amplified and sequenced, with subtype IIaA17G2R1 (n = 3) and subtypes XXa4 (n = 1) and XXa5 (n = 1) being identified, respectively. Conclusions: The present finding of three zoonotic Cryptosporidium species in dogs implied that dogs infected with Cryptosporidium spp. may pose a threat to human health. C. suis was identified in dogs in this study for the first time, expanding the host range of this species. Identification of C. parvum subtype IIaA17G2R1 and C. canis subtypes XXa4 and XXa5 will be helpful to explore the source attribution of infection/contamination and assess the transmission dynamics of C. parvum and C. canis in the investigated areas in the future. [ABSTRACT FROM AUTHOR]

Simple Summary: Trichomonads are among the most prevalent intestinal parasites with a worldwide distribution which can infect many animals, resulting in economic losses and threatening public health. The donkey raising industry in Shanxi Province is relatively well-developed; however, it is not yet known whether donkeys in Shanxi Province were infected with Tetratrichomonas buttreyi and Pentatrichomonas hominis. Thus, 815 fecal samples were collected from donkeys in three representative geographical locations in Shanxi Province to determine the prevalence and associated risk factors of T. buttreyi and P. hominis in donkeys using molecular approaches. The overall prevalence of T. buttreyi and P. hominis in donkeys in Shanxi Province was 25.4% and 0.7%, respectively. Genetic analysis revealed that all P. hominis sequences obtained in this study were identified as genotype CC1, suggesting possible zoonotic potential. This is the first report of T. buttreyi and P. hominis prevalence in donkeys worldwide, which not only extends the geographical distribution of trichomonads but also expands the host spectrum. The findings also have implications for the prevention and control of trichomonad infections in donkeys in Shanxi Province. Two species of trichomonads, Tetratrichomonas buttreyi and Pentatrichomonas hominis, are common intestinal parasites that can impact animal health and productivity. Severe infection by these parasites can lead to diarrhea and wasting in affected animals. Notably, P. hominis is known to cause diarrhea and has the potential to be transmitted between animals and humans. Donkeys hold significant economic importance in China's agricultural sector. However, whether donkeys are infected with T. buttreyi and P. hominis remains unknown globally. To address this gap in knowledge, 815 fecal samples were collected from donkeys in three representative regions in Shanxi Province, North China. Then, the presence and genetic characteristics of T. buttreyi and P. hominis were examined using species-specific PCR primers amplifying the small subunit ribosomal RNA genes. The overall prevalence was detected to be 25.4% (207/815) for T. buttreyi and 0.7% (6/815) for P. hominis in donkeys in Shanxi Province. All obtained P. hominis sequences were identified as genotype CC1. Genetic analysis revealed that all P. hominis isolates from donkeys were clustered into the same branch with isolates detected in humans, suggesting possible zoonotic transmission. This study is the first to report the occurrence and prevalence of T. buttreyi and P. hominis in donkeys globally. These findings expand the host range of trichomonads and improve our understanding of their genetic diversity and zoonotic potential, providing essential baseline data for the prevention and control of these parasites in donkeys in the region. [ABSTRACT FROM AUTHOR]