Indigenous metal-tolerant mine water bacterial populations under varying metal stresses.

The present study investigated the indigenous metal-tolerant bacterial populations in the mine-water microbiome. Our intention was to assess the effects of the metal concentrations in mine water on the bacterial community of mine waters. The bacterial communities in Vanadium and Gold mine-water samples were exposed to different heavy-metal Arsenic, Cadmium, Chromium, Nickel, Mercury and Vanadium at two different concentrations (5 and 25 mM). The 16S rRNA amplicon from mine waters were sequenced using the Illumina's NGS MiSeq platform. Data analysis revealed a high diversity in the bacterial populations associated with the different heavy metals at different concentrations. The taxonomic profiles obtained after the exposure were different in different salts, but mostly dominated by Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria and Firmicutes at variable relative abundance. Principal Component Analysis (PCoA) predicts the clear community shift after exposure with heavy metals salts and emergence of tolerant community depending upon the specific community present in the original mine water.

Towards genomic medicine: a tailored next-generation sequencing panel for hydroxyurea pharmacogenomics in Tanzania.

BACKGROUND: Pharmacogenomics of hydroxyurea is an important aspect in the management of sickle cell disease (SCD), especially in the era of genomic medicine. Genetic variations in loci associated with HbF induction and drug metabolism are prime targets for hydroxyurea (HU) pharmacogenomics, as these can significantly impact the therapeutic efficacy and safety of HU in SCD patients. METHODS: This study involved designing of a custom panel targeting BCL11A, ARG2, HBB, HBG1, WAC, HBG2, HAO2, MYB, SAR1A, KLF10, CYP2C9, CYP2E1 and NOS1 as potential HU pharmacogenomics targets. These genes were selected based on their known roles in HbF induction and HU metabolism. The panel was designed using the Illumina Design Studio (Illumina, San Diego, CA, USA) and achieved a total coverage of 96% of all genomic targets over a span of 51.6 kilobases (kb). This custom panel was then sequenced using the Illumina MiSeq platform to ensure high coverage and accuracy. RESULTS: We are reporting a successfully designed Illumina (MiSeq) HU pharmacogenomics custom panel encompassing 51.6 kilobases. The designed panel achieved greater than 1000x amplicon coverage which is sufficient for genomic analysis. CONCLUSIONS: This study provides a valuable tool for research in HU pharmacogenomics, especially in Africa where SCD is highly prevalent, and personalized medicine approaches are crucial for improving patient outcomes. The custom-designed Illumina (MiSeq) panel, with its extensive coverage and high sequencing depth, provides a robust platform for studying genetic variations associated with HU response. This panel can contribute to the development of tailored therapeutic strategies, ultimately enhancing the management of SCD through more effective and safer use of hydroxyurea.

Comparison of Metabarcoding and Microscopy Methodologies to Analyze Diatom Communities in Five Estuaries Along the Southern Coast of the Korean Peninsula.

The study of microalgal communities is critical for understanding aquatic ecosystems. These communities primarily comprise diatoms (Heterokontophyta), with two methods commonly used to study them: Microscopy and metabarcoding. However, these two methods often deliver different results; thus, their suitability for analyzing diatom communities is frequently debated and evaluated. This study used these two methods to analyze the diatom communities in identical water samples and compare the results. The taxonomy of the species constituting the diatom communities was confirmed, and both methods showed that species belonging to the orders Bacillariales and Naviculales (class Bacillariophyceae) are the most diverse. In the lower taxonomic levels (family, genus, and species), microscopy tended to show a bias toward detecting diatom species (Nitzschia frustulum, Nitzschia inconspicua, Nitzschia intermedia, Navicula gregaria, Navicula perminuta, Navicula recens, Navicula sp.) belonging to the Bacillariaceae and Naviculaceae families. The results of the two methods differed in identifying diatom species in the communities and analyzing their structural characteristics. These results are consistent with the fact that diatoms belonging to the genera Nitzschia and Navicula are abundant in the communities; furthermore, only the Illumina MiSeq data showed the abundance of the Melosira and Entomoneis genera. The results obtained from microscopy were superior to those of Illumina MiSeq regarding species-level identification. Based on the results obtained via microscopy and Illumina MiSeq, it was revealed that neither method is perfect and that each has clear strengths and weaknesses. Therefore, to analyze diatom communities effectively and accurately, these two methods should be combined.

Environmental DNA metabarcoding reveals diverse phytoplankton assemblages and potentially harmful algal distribution along the urban coasts of Türkiye.

Marine phytoplankton are widely used to monitor the state of the water column due to their rapid changes in response to environmental conditions. In this study, we aimed to investigate the coastal phytoplankton assemblages, including bloom-forming species using high-throughput sequencing of 18S rRNA genes targeting the V4 region and their relationship with environmental variables along the Istanbul coasts of the Sea of Marmara. A total of 118 genera belonging to six phyla were detected. Among them, Dinoflagellata (36) and Bacillariophyta (26) were represented with the highest number of genera. According to the relative abundance of DNA reads, the most abundant taxa were Dinoflagellata_phylum (18.1%), Emiliania (8.4%), Biecheleria (8.4), and Noctiluca (8.1%). The ANOSIM test showed that there was a significant temporal difference in the assemblages, while the driving environmental factors were pH, water temperature, and salinity. According to the TRIX index, the trophic state of the coasts was highly mesotrophic and eutrophic. In addition, 45 bloom-forming and HAB taxa were detected and two species of Noctiluca and Emiliania, which frequently cause blooms in the area, were recorded in high abundance. Our results provide insight into the phytoplankton assemblages along the urbanized coastlines by analysing the V4 region of 18S rRNA. This data can support future studies that use both traditional methods and metabarcoding, employing various primers and targeting different genes and regions.

Sequencing-induced artefacts in NGS STR data.

Significant progress has been made in recent years in the development of techniques for Next Generation Sequencing (NGS), or Massively Parallel Sequencing (MPS), of forensically relevant short tandem repeat (STR) loci. However, as these technologies are investigated and adopted by forensic laboratories, new challenges unfold that require further scrutiny. In the analysis of DNA profiles generated using the MiSeq FGx sequencing system, we have observed noise sequences with relatively high readcounts that are challenging to distinguish from genuine alleles. These high read count noise sequences appear as allele sequences with one or a few substituted bases compared to a known allele sequence within the profile. An examination of ForenSeq DNA Signature Prep Kit STR noise sequences revealed that the substituted base of a parent allele can align to the same position on the sequence across noise sequences. This suggests that these substitution events occur at specific positions within the amplicon, resulting in multiple noise reads with substitutions at the same position. Mapping of the noise events onto the original raw read positions revealed a high number of events, or "noise spikes", occurring at specific positions within a given sequencing run. These noise spikes affected reads across the entire run, agnostic of locus or sample, while the position, occurrence, and amplitude of the spikes differed across runs. The majority of noise sequences with high read counts in a DNA profile were generated from base changes at these spike positions, and could be classified as "noise spike artefacts". In this paper we present evidence of the noise spike artefacts and their genesis during the sequencing process in the sequencing-by-synthesis (SBS) cycles, as well as the methods developed to detect them. The information and methods will assist laboratories with detecting noise spikes in MiSeq FGx sequencing runs, differentiating authentic allele sequences from noise spike artefacts, and developing protocols for analyst review and handling of MiSeq FGx data.

Development and application of a whole genome amplicon sequencing method for infectious salmon anemia virus (ISAV).

Infectious salmon anemia (ISA) is an infectious disease primarily affecting farmed Atlantic salmon, Salmo salar, which is caused by the ISA virus (ISAV). ISAV belongs to the Orthomyxoviridae family. The disease is a serious condition resulting in reduced fish welfare and high mortality. In this study, we designed an amplicon-based sequencing protocol for whole genome sequencing of ISAV. The method consists of 80 ISAV-specific primers that cover 92% of the virus genome and was designed to be used on an Illumina MiSeq platform. The sequencing accuracy was investigated by comparing sequences with previously published Sanger sequences. The sequences obtained were nearly identical to those obtained by Sanger sequencing, thus demonstrating that sequences produced by this amplicon sequencing protocol had an acceptable accuracy. The amplicon-based sequencing method was used to obtain the whole genome sequence of 12 different ISAV isolates from a small local epidemic in the northern part of Norway. Analysis of the whole genome sequences revealed that segment reassortment took place between some of the isolates and could identify which segments that had been reassorted.

Effects of tefluthrin and guadipyr on the midgut bacteria of adult Apis mellifera.

The objective of this study is to assess the potential impact of tefluthrin and guadipyr on the gut microbial composition and metabolism in adult Apis mellifera ligustica, thereby elucidating the underlying mechanisms of insecticide action and its practical implications for bee protection. In this investigation, A. mellifera were subjected to one of three dietary conditions: (1) control sugar water, (2) tefluthrin-infused sugar water, or (3) guadipyr-infused sugar water. After a 10-day exposure period, genomic DNA from the gut bacteria was extracted. High-throughput sequencing was employed to evaluate the potential influence of tefluthrin and guadipyr treatments on the diversity and abundance of gut bacteria. Among the A. mellifera specimens, a total of twenty species of gut bacteria were identified, spanning across five phyla, six classes, eleven orders, eleven families, and fifteen genera. The dominant phyla within the gut bacterial community were Proteobacteria and Bacteroidetes. In comparison to the control group, both the tefluthrin-treated and deltamethrin-treated groups exhibited alterations in the composition of their gut bacterial flora. At the phylum level, there was a significant decrease in the relative abundance of Cyanobacteria (P < 0.05). On the genus level, the tefluthrin group displayed a significant increase in the relative abundance of Bartonella and Serratia (P < 0.05). In the guadipyr-treated group, the relative abundance of Gilliamella and Frischella increased significantly (P < 0.05), while the relative abundance of norank_o_Chloroplast and Enterobacter decreased significantly (P < 0.05). Further analysis of cluster of orthologous genes predicted functional changes in gut microbial metabolism following tefluthrin exposure but no significant changes after guadipyr exposure. Consequently, exposure to tefluthrin and guadipyr can induce shifts in both the composition and metabolic activity of the gut bacteria in A. mellifera. Notably, the impact of tefluthrin on the gut bacteria of A. mellifera appears to be more pronounced compared to that of guadipyr.

Microbiota Association and Profiling of Gingival Sulci and Root Canals of Teeth with Primary or Secondary/Persistent Endodontic Infections.

INTRODUCTION: Microbiota associated with primary endodontic infection (PEI) and secondary/persistent endodontic infection (SPEI) must be characterized to elucidate pathogenesis in apical periodontitis and bacterial biomarkers identified for diagnostic and therapeutic applications. METHODS: This study analyzed the microbial community profiles of root canals and gingival sulci (sulcus-E) for teeth with PEI (n = 10) or SPEI (n = 10), using the Illumina MiSeq platform. Bacterial samples from gingival sulci (sulcus-C) of healthy contralateral teeth served as controls. RESULTS: There were 15 phyla, 177 genera, and 340 species identified. The number and diversity of bacteria in root canals did not differ significantly between PEI and SPEI. Proteobacteria, Firmicutes, Fusobacteria, Bacteroidetes, and Actinobacteria were the dominant phyla in both groups. At the genus level, Lancefieldella, Bifidobacterium, Stomatobaculum, and Schaalia were enriched in root canals with SPEI. Of significance, Lancefieldella was observed in both root canals and sulcus-E of teeth with SPEI. At the species level, Neisseria macacae, Streptococcus gordonii, Bifidobacterium dentium, Stomatobaculum longum, and Schaalia odontolytica were increased significantly in root canals with SPEI compared to PEI. Oribacterium species, Streptococcus salivarius, Lancefieldella parvula, Prevotella denticola, and Oribacterium asaccharolyticum were more abundant in sulcus-E of teeth with SPEI compared to PEI. CONCLUSIONS: There were distinctive and differing predominant bacterial species associated with the root canals and gingival sulci between teeth with PEI and SPEI. Specific bacteria identified in sulcus-E and root canals of teeth with SPEI could serve as noninvasive diagnostic biomarkers for detecting SPEI.

Investigating Dirofilaria immitis isolates infecting domestic canines and their susceptibility/resistance patterns to macrocyclic lactones in the northern region of the Mississippi Delta area (southeast Missouri).

Previous reports of macrocyclic lactone (ML) resistance in Dirofilaria immitis, the parasitic nematode which causes heartworm disease, have mainly been from the southern Mississippi Delta region. Southeast Missouri (SEMO), forming the northern boundary of this region, has not previously been well studied. The area is an ideal propagation region for heartworm infection and possibly for the spread of ML resistance. To assess whether D. immitis isolates infecting domestic canines in SEMO exhibit evidence of resistance to MLs, domestic canines, presented to veterinary facilities testing positive for heartworms through antigen and microfilariae (MF) examination, were utilized in the study. Using a descriptive epidemiological cross-sectional study, from March 2021 through February 2022, blood sample collection from 96 canines living in SEMO testing positive for heartworms were analyzed. MiSeq technology was utilized to sequence specific genetic markers associated with susceptibility/resistance for MLs in D. immitis isolates. Genomic data revealed most D. immitis isolates had genotypic profiles consistent with resistance to MLs. Of the 96 samples tested, 91 (94.8%) had a resistant genotype, 4 (4.2%) had a mixed genotype, and 1 sample (1%) genotyped as susceptible. While detailed and reliable medical histories were not available for most canines, detailed medical history from 2 canines indicated evidence of phenotypic resistance that was consistent with their genotypes. However, in vivo preventive tests are needed to confirm a high frequency of phenotypic ML resistance in D. immitis from this region. Increasing resistance patterns to MLs indicate the approach to heartworm prevention/treatment protocol should be reconsidered. New measures may be required to stop heartworm disease.

Hepatic transcriptome, transcriptional effects and antioxidant responses in Poecilia vivipara exposed to sanitary sewage.

Aquatic environments are subject to threats from multiple human activities, particularly through the release of untreated sanitary sewage into the coastal environments. These effluents contain a large group of natural or synthetic compounds referred to as emerging contaminants. Monitoring the types and quantities of toxic substances in the environment, especially complex mixtures, is an exhausting and challenging task. Integrative effect-based tools, such as biomarkers, are recommended for environmental quality monitoring programs. In this study, fish Poecilia vivipara were exposed for 24 and 96 h to raw untreated sewage diluted 33 % (v/v) in order to identify hepatic genes to be used as molecular biomarkers. Through a de novo hepatic transcriptome assembly, using Illumina MiSeq, 54,285 sequences were assembled creating a reference transcriptome for this guppy species. Transcripts involved in biotransformation systems, antioxidant defenses, ABC transporters, nuclear and xenobiotic receptors were identified and evaluated by qPCR. Sanitary sewage induced transcriptional changes in AhR, PXR, CYP2K1, CYP3A30, NQO1, UGT1A1, GSTa3, GSTmu, ST1C1, SOD, ABCC1 and SOX9 genes from liver of fish, particularly after 96 h of exposure. Changes in hepatic enzyme activities were also observed. The enzymes showed differences in fish exposed to both periods, while in the gills there was a prevalence of significant results after 96 h. The observed differences were associated to gender and/or to sewage exposure. The obtained results support the use of P. vivipara as sentinel and model organism for ecotoxicological studies and evidence the importance of understanding the differential responses associated to gender.

Identification of the Microbiota in Coconut Water, Kefir, Coconut Water Kefir and Coconut Water Kefir-Fermented Sourdough Using Culture-Dependent Techniques and Illumina-MiSeq Sequencing.

The principal objective of this study was to isolate and identify the microorganisms present in commercial kefir grains, a novel kefir-fermented coconut water (CWK) and a novel coconut water kefir-fermented sourdough using phenotypic identification and Sanger sequencing and examine the microbial diversity of CWK and CWK-fermented sourdough throughout the fermentation process using the MiSeq Illumina sequencing method. The phenotypic characterisation based on morphology identified ten isolates of LAB, five AAB and seven yeasts from kefir (K), CWK and CWK-fermented sourdough (CWKS). The results confirm the presence of the LAB species Limosilactobacillus fermentum, Lactobacillus. plantarum, L. fusant, L. reuteri and L. kunkeei; the AAB species Acetobacter aceti, A. lovaniensis and A. pasteurianus; and the yeast species Candida kefyr, Rhodotorula mucilaginosa, Saccharomyces cerevisiae, C. guilliermondii and C. colliculosa. To the best of our knowledge, the identification of Rhodotorula from kefir is being reported for the first time. This study provides important insights into the relative abundances of the microorganisms in CWKS. A decrease in pH and an increase in the titratable acidity for CWK- and CWK-fermented sourdough corresponded to the increase in D- and L-lactic acid production after 96 h of fermentation. Significant reductions in the pHs of CWK and CWKS were observed between 48 and 96 h of fermentation, indicating that the kefir microorganisms were able to sustain highly acidic environments. There was also increased production of L-lactic acid with fermentation, which was almost twice that of D-lactic acid in CWK.

Developmental validation of the ForenSeq® Kintelligence kit, MiSeq FGx® sequencing system and ForenSeq Universal Analysis Software.

Forensic Investigative Genetic Genealogy, a recent sub discipline of forensic genomics, leverages the high throughput and sensitivity of detection of next generation sequencing and established genetic and genealogical approaches to support the identification of human remains from missing persons investigations and investigative lead generation in violent crimes. To facilitate forensic DNA evidence analysis, the ForenSeq® Kintelligence multiplex, consisting of 10,230 SNPs, was developed. Design of the ForenSeq Kintelligence Kit, the MiSeq FGx® Sequencing System and the ForenSeq Universal Analysis Software is described. Developmental validation in accordance with SWGDAM guidelines and forensic quality assurance standards, using single source samples, is reported for the end-to-end workflow from library preparation to data interpretation. Performance metrics support the conclusion that more genetic information can be obtained from challenging samples compared to other commercially available forensic targeted DNA assays developed for capillary electrophoresis (CE) or other current next generation sequencing (NGS) kits due to the higher number of markers, the overall shorter amplicon sizes (97.8% <150 bp), and kit design. Data indicate that the multiplex is robust and fit for purpose for a wide range of quantity and quality samples. The ForenSeq Kintelligence Kit and the Universal Analysis Software allow transfer of the genetic component of forensic investigative genetic genealogy to the operational forensic laboratory.

Comparison of the performance of MiSeq and NovaSeq in oral microbiome study.

Objective: Next generation sequencing is commonly used to characterize the microbiome structure. MiSeq is most commonly used to analyze the microbiome due to its relatively long read length. Illumina also introduced the 250 × 2 chip for NovaSeq. The purpose of this study was to compare the performance of MiSeq and NovaSeq in the context of oral microbiome study. Methods: Total read count, read quality score, relative bacterial abundance, community diversity, and correlation between two platforms were analyzed. Phylogenetic trees were analyzed for Streptococcus and periodontopathogens. Results: NovaSeq produced significantly more read counts and assigned more operational taxonomic units (OTUs) compared to MiSeq. Community diversity was similar between MiSeq and NovaSeq. NovaSeq were able to detect more unique OTUs compared to MiSeq. When phylogenetic trees were constructed for Streptococcus and periodontopathogens, both platforms detected OTUs for most of the clades. Conclusion: Taken together, while both MiSeq and NovaSeq platforms effectively characterize the oral microbiome, NovaSeq outperformed MiSeq in terms of read counts and detection of unique OTUs, highlighting its potential as a valuable tool for large scale oral microbiome studies.

Uncovering the microbial diversity of Czech Republic archives: A study of metabolically active airborne microbes.

Despite the diligent efforts of libraries, archives, and similar institutions to preserve cultural monuments, biodeterioration continues to pose a significant threat to these objects. One of the main sources of microorganisms responsible for the biodeterioration process is the presence of airborne microorganisms. Therefore, this research aims to monitor and compare outcomes of both culture-dependent (utilising various cultivation strategies) and culture-independent approaches (RNA-based sequencing) to identifying metabolically active airborne microorganisms in archives in the Czech Republic. Through this study, several species that have the potential to pose risks to both cultural heritage objects and the health of institution employees were found. Additionally, the efficacy of different cultivation media was demonstrated to be varied across archive rooms, highlighting the necessity of employing multiple cultivation media for comprehensive analyses. Of noteworthy importance, the resuscitating-promoting factor (Rpf) proved to be a pivotal tool, increasing bacterial culturability by up to 30% when synergistically employed Reasoner's 2A agar (R2A) and R2A + Rpf media. Next, the study emphasises the importance of integrating both culture-dependent and culture-independent approaches. The overlap between genera identified by the culture-dependent approach and those identified also by the culture-independent approach varied from 33% to surpassing 94%, with the maximum alignment exceeding 94% in only one case. Our results highlight the importance of actively monitoring and assessing levels of microbial air contamination in archives to prevent further deterioration of cultural heritage objects and to promote improved conditions for employees in archives and similar institutions.

16S-Metagenomic data profiling of the bacterial community in ready-to-eat vegetable salads sold in Kampala, Uganda.

This article presents a dataset on bacterial community structure associated with Ready-to-eat (RTE) vegetable salads sold in Kampala City, Uganda. The Illumina Miseq sequencing of 16S rRNA gene amplicon unveiled the bacterial communities and generated a metagenomic library from RTE vegetable salads to understand the diversities and distribution. The metagenome contained a total of 23,805 sequences with 35,420 Taxonomic units (OTUs). Metagenome sequence information is obtainable at NCBI under the Bioproject assigned accession number PRJNA1064313. Taxonomic hits distribution from VSEARCH analysis at phylum level classification of NN-3 discovered predominantly Proteobacteria (65.34%) followed by Firmicutes (31.60%) and Bacteroidota (0.14%). Deinococcota (0.01%) and Planctomycetota (0.01%) were also detected. Also, VSEARCH-assisted analysis of NN-4 detected a higher prevalence of Firmicutes (65.68%) than Proteobacteria (33.25%), while Bacteroidota (0.04%) indicating the presence of contaminants of faecal sources.

Responses of soil microbiome to copper-based materials (nano and bulk) for agricultural applications: An indoor-mesocosm experiment.

The foreseen increasing application of copper-based nanomaterials (Cu-NMs), replacing or complementing existing Cu-agrochemicals, may negatively impact the soil microbiome. Thus, we studied the effects on soil microbiome function and composition of nano copper oxide (nCuO) or copper hydroxide NMs in a commercial (Kocide®3000) or a lab-synthetized formulation (nCu(OH)2) or bulk copper hydroxide (Cu(OH)2-B), at the commonly recommended Cu dose of 50 mg(Cu)kg-1 soil. Microbial responses were studied over 28 days in a designed indoor mesocosm. On day-28, in comparison to non-treated soil (CT), all Cu-treatments led to a reduction in dehydrogenase (95% to 68%), arylsulfatase (41% to 27%), and urease (40% to 20%) activity. There was a 32% increase in the utilization of carbon substrates in the nCuO-treatment and an increased abundance of viable bacteria in the nCu(OH)2-treatment (75% of heterotrophic and 69% of P-solubilizing bacteria). The relative abundance of Acidobacteria [Kocide®3000, nCuO, and Cu(OH)2-B treatments] and Flavobacteriia [nCu(OH)2-treatment] was negatively affected by Cu exposure. The abundance of Cu-tolerant bacteria increased in soils treated with Kocide®3000 (Clostridia) and nCu(OH)2 (Gemmatimonadetes). All Cu-treated soils exhibited a reduced abundance of denitrification-related genes (0.05% of nosZ gene). The DTPA-extractable pool of ionic Cu(II) varied among treatments: Cu(OH)2-B > Kocide®3000 âˆ¼ nCuO>nCu(OH)2, which may explain changes on the soil microbiome composition, at the genera and OTU levels. Thus, our study revealed that Cu-materials (nano and bulk) influence the soil microbiome with implications on its ecological role. It highlights the importance of assessing the impact of Cu-materials under dynamic and complex exposure scenarios and emphasizes the need for specific regulatory frameworks for NMs.

Application of Rice Straw Inhibits Clubroot Disease by Regulating the Microbial Community in Soil.

Straw return is an effective agricultural management practice for alleviating soil sickness, but only a few studies have focused on the incorporation of straw with deep plowing and rotary tillage practices in vegetable production. To determine the effects of rice straw return on Chinese cabbage clubroot, a field experiment for three consecutive years in the same area was performed. Soil microbial high-throughput sequencing, quantitative real-time polymerase chain reaction (PCR) and other methods were used to detect Chinese cabbage plant growth, clubroot occurrence, soil chemical properties and soil microbial diversity and abundance. The results showed that straw addition could significantly reduce the clubroot disease incidence. Through Illumina Miseq sequencing, the diversity of the fungi decreased obviously. The relative abundance of the phyla Proteobacteria and Firmicutes was strikingly reduced, while that of Chloroflexi was significantly increased. Redundancy analysis suggests that soil properties may also affect the soil microbial composition; changes in the microbial structure of bacteria and fungi were associated with the available phosphorus. In conclusion, the continuous addition of rice straw can promote the growth and control the occurrence of clubroot, which is closely related to the microbial composition, and the inhibition effect is proportional to the age of addition.

Characterization of bacterial diversity and screening of cellulose-degrading bacteria in the gut system of Glenea cantor (Fabricius) larvae.

The intestinal bacteria of longhorn beetles would be ideal targets for pest control and lignocellulosic resources by destroying or exploiting their cellulose-degrading function. This article aims to investigate the diversity and community structure of intestinal bacteria the oligophagous longhorn beetle Glenea cantor. Additionally, it seeks to identify the presence of lignocellulose-degrading bacteria in the gut, and explore their role in consuming host kapok trees Bombax malabaricum. In this study, the bacterial community from G. cantor was examined by Illumina sequencing of 16S ribosomal RNA (rRNA) targeting the V3 and V4 regions. A total of 563,201 valid sequences and 814 OTUs were obtained. The dominant phyla were Proteobacteria, and the dominant genera were Acinetobacter and Lactococcus. The analysis of microbial diversity revealed a high bacterial diversity in the samples, with the gut bacteria playing a crucial role in the physiological activities of the host, particularly, 9 genera of intestinal bacteria with cellulose degradation function were found, highlighting their vital role in cellulose degradation. Five strains of cellulose-degrading bacteria, belonging to the genus Pseudomonas, were obtained from the intestinal tract of G. cantor larvae using traditional isolation and culture techniques as well as 16S rDNA sequencing. Among these strains, A4 exhibited a cellulase activity of 94.42 ± 0.42 U/mL, while A5 displayed the highest filter paper enzyme activity of 127.46 ± 3.54 U/mL. These results offered valuable insights into potential targets for pest control through internal attack digestion and cellulose-degrading bacteria in longhorn beetles.

Temporal changes in ewe vaginal microbiota throughout gestation.

Introduction: Numerous factors are known to influence reproductive efficiency in ewes, but few studies have investigated the potential role of vaginal microbiota in sheep reproductive success. The objective of this study was to thoroughly characterize the ewe vaginal microbiota throughout the course of pregnancy. Methods: Vaginal samples were collected from 31 pregnant Hampshire and Hampshire X Suffolk crossbred ewes on a weekly basis from pre-breeding to pregnancy testing and then biweekly until just after lambing. To characterize the vaginal microbial communities, DNA was extracted and 16S rRNA gene Illumina MiSeq amplicon sequencing was performed. Results and Discussion: Alpha diversity metrics indicated an increase in species richness, evenness, and overall diversity throughout gestation. Distinct shifts in the bacterial communities were observed during gestation and were segregated into three periods: early gestation, a transitional period and mid/late gestation. During early gestation, Actinobacillus, Histophilus, and unclassified Leptotrichiaceae were found in greater relative abundance. During the transitional period, a population shift occurred characterized by increasing relative abundance of Streptococcus and Staphylococcus. During mid/late gestation, Staphylococcus, Streptococcus, and Ureaplasma had the greatest relative abundance. These shifts in the microbial population throughout the ewe's gestation are likely related to hormonal changes triggered by the growing conceptus, specifically increasing blood concentration of progesterone. The transitional period shift in vaginal microbial communities potentially aligns with the placental take-over of progesterone production from the corpus luteum at approximately day 50 after conception (gestational week 7). Understanding the observed variability of the vaginal microbiota throughout pregnancy will allow for future comparison of ewes that did not become pregnant or had abnormal pregnancies, which could lead to the discovery of potential bacterial biomarkers for pregnancy outcome; this understanding could also lead to development of probiotics to improve sheep reproductive success.