Search PubMedSearch

SEARCH · Search PubMed

Results for “whole genome analysis”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Whole-Genome Analysis and Growth-Promoting Mechanism of Klebsiella pneumoniae YMK25 from Maize Rhizobacteria.

Plant growth-promoting rhizobacteria (PGPR) are microorganisms that enhance plant growth through various mechanisms. In the context of global agriculture, which faces fertilizer dependency and environmental pollution, developing eco-friendly microbial fertilizers has become crucial for enhancing agricultural sustainability. To identify highly effective PGPR, we isolated 102 bacterial strains from maize rhizosphere soil using the dilution plating method. The strains were screened for growth-promoting abilities using functional media, resulting in the selection of strain YMK25 for its exceptional capabilities in nitrogen fixation, solubilization of inorganic and organic phosphorus, indole-3-acetic acid (IAA) production, and siderophore production. Strain YMK25 produced IAA at a concentration of 80.49 ± 0.68 μg/mL and exhibited a relative siderophore expression level of 43.68%. Morphological analysis, 16S rDNA gene sequence analysis, and whole-genome sequencing confirmed that strain YMK25 is Klebsiella pneumoniae. Whole-genome analysis revealed a total genome length of 5,115,280 bp, a GC content of 57.61%, and it contained 4746 coding genes. Gene annotation results indicated genes involved in siderophore synthesis, phosphatase activity, and other plant growth-promoting functions, which align with the verified characteristics of strain YMK25. Furthermore, this strain exhibited significant metabolic capabilities. The pot experiment demonstrated that strain YMK25 promotes maize plant growth and assists in nutrient fixation in these plants. In conclusion, strain YMK25 is a high-quality PGPR with substantial potential for application in agricultural production, presenting promise for widespread use in sustainable agriculture.

Klebsiella pneumoniae

Whole genome analysis of a multidrug-resistant blaNDM-5-carrying Escherichia coli Sequence Type (ST) 167 strain isolated from seafood in Mumbai, India.

BACKGROUND: E. coli ST167 is an emerging extraintestinal pathogenic Escherichia coli (ExPEC) clone. This study reports the whole genome sequence analysis of a multidrug-resistant, blaNDM-5 harboring E. coli ST167 (EC121) isolated from seafood. The antibiotic susceptibility pattern was determined using the standard disc diffusion method. Genomic DNA was extracted, purified, and sequenced using the Illumina platform. The whole genome sequence was analyzed to determine the genome characteristics, including sequence type, serotype, phylogroup, antibiotic resistance genes, virulence attributes, and phylogenetic analysis. RESULTS: Phenotypically, this isolate was resistant to 26 of the 33 antibiotics tested, which correlated well with in-silico prediction. Multilocus sequence typing (MLST) analysis revealed that this strain belonged to sequence type 167, serotype O101:H9, and phylogroup A and harbored different virulence genes, suggesting it was a potential human pathogen. Many acquired antibiotic resistance genes were detected, including blaNDM-5, blaCMY-42, blaOXA-1, blaTEM-116, catA1, sul2, and tet(B). Point mutations in gyrA and parC responsible for quinolone resistance were also detected. CONCLUSION: The combinations of virulence and antibiotic resistance genes in this strain highlight the significant risk associated with emerging E. coli clonal types contaminating the seafood supply chain. Fecal contamination of seafood can contribute to the community dissemination of multidrug-resistant E. coli, necessitating effective monitoring measures.

Seafood

Longitudinal whole-genome analysis of bluetongue virus identifies conserved serotype-specific genomes and distinct genomic constellations within a Colorado sheep flock (2021-2023).

Bluetongue virus (BTV) is a segmented double-stranded RNA virus of ruminants transmitted by Culicoides spp. biting midges. Although the genome consists of ten segments, classification into serotypes is primarily based on genome segment 2. However, reassortment among genomic segments is a major driver of BTV evolution and diversity. This study used longitudinal whole-genome sequencing to characterize BTV genomes collected from 2021 to 2023 within a single sheep flock in Colorado, where multiple serotypes co-circulate. Whole-genome sequences were generated from fourteen blood samples representing four serotypes: BTV-6, -11, -13, and -17. Longitudinal sampling identified multiple BTV serotypes within individual sheep across consecutive years. Tanglegram analysis comparing segment phylogenies to the segment 2 tree demonstrated incongruent topologies across all genomic segments, suggestive of reassortment or the circulation of distinct genomic constellations. Nucleotide-level comparisons revealed high sequence homology among same-serotype samples from the same year, while the greatest genetic divergence was observed among BTV-17 genomes collected in different years. Additionally, all BTV-13 genomes contained a previously undescribed nonsynonymous substitution in segment 10 predicted to extend the encoded protein by three amino acids. Together, these findings demonstrate that highly conserved BTV genomes and distinct genomic constellations can be detected at the flock level across multiple years. This longitudinal whole-genome approach reveals the genetic complexity of endemic BTV populations, including novel variants and genomic patterns consistent with reassortment that are lost with conventional serotyped-based approaches, highlighting the need to integrate whole-genome characterization into endemic BTV monitoring programs.

Animals

Whole-Genome Analysis of Bacillus Licheniformis Ali5 and Synthesis of Lichenysin via Genome Shuffling.

Whole-genome sequencing of Bacillus licheniformis Ali5 was performed via MGI-seq PE150 and Nanopore single-molecule real-time sequencing. The strain has a 4,114,664 bp circular genome encoding 4030 protein-coding genes. Functional annotation across NR, COG, GO, KEGG, CARD, BacMet, and CAZy databases identified 4025, 2812, 988, 1242, 72, 69, and 94 corresponding genes, respectively, and antiSMASH 6.0 revealed multiple antimicrobial biosynthetic gene clusters, including intact lichenysin and lichenicidin VK21 A1/A2 gene clusters. Three rounds of recursive protoplast fusion-based genome shuffling, paired with a dual-index screening system, significantly improved strain growth and lichenysin biosynthesis. Recombinants exhibited shortened lag phase, enhanced proliferation, improved stationary-phase stability, and higher diauxic peak biomass. PP3-176 and PP3-186 showed 4.6%-8.1% higher 12-h shake-flask titer and 3.1%-4.0% higher maximum titer than the parental average, with excellent fermentation stability. 1-L bioreactor validation confirmed strong scale-up potential. PP3-186 achieved 27.2% and 31.6% titer increases at 12 h and 20 h, while PP3-176 yielded 20.4% and 14.6% improvements with robust metabolic performance. This study validates genome shuffling as an effective strategy for enhancing lichenysin production, providing candidate strains and technical support for industrial application.

Bacillus licheniformis

Whole-Genome Analysis Reveals Antimicrobial Resistance and Population Structure of Environmental and Veterinary Acinetobacter baumannii.

Acinetobacter (A.) baumannii is an important multidrug-resistant pathogen increasingly recognized across animal and environmental settings, and carbapenem-resistant A. baumannii (CRAB) is classified as a critical-priority pathogen by the World Health Organization. This study investigated the antimicrobial resistance (AMR) and genomic characteristics of 122 A. baumannii isolates comprising 72 veterinary and 50 environmental isolates collected in Andhra Pradesh, India. Antimicrobial susceptibility testing, whole-genome sequencing (WGS), resistance and virulence gene profiling, multilocus sequence typing (MLST), core-genome analysis, single nucleotide polymorphism (SNP) phylogeny, and pan-genome analysis were performed. Overall, 58.2% of isolates were multidrug-resistant (MDR), and 41.8% were extensively drug-resistant (XDR). Sequence type (ST) 52 predominated among veterinary isolates, whereas ST2 was more frequent among environmental isolates. The presence of carbapenem-resistant isolates along with the ST2 lineage enhances the similarity to clinical A. baumannii. Several intrinsic resistance genes, including blaOXA-23, armA, aph(3″)-Ib, aph(6)-Id, tet(B), mph(E), and msr(E), were more prevalent in the ST2-associated population. Virulence-associated determinants were widely conserved. Core-genome MLST (cgMLST) and core-genome SNP (cgSNP) analyses identified highly related isolates within both lineages, while pairwise SNP differences were 0-7. Pan-genome analysis identified 4204 gene clusters and distinct accessory gene patterns between ST2 and ST52. These findings indicate that resistance gene distribution was closely associated with lineage structure and support integrated genomic surveillance of A. baumannii across animal and environmental reservoirs.

Acinetobacter baumannii

Exploring the mechanism of aroma production in fermented cherry juice by L. brevis LD1.0600 using flavomics and whole genome analysis.

This study focused on L.brevis LD1.0600 with excellent fermentation traits: it analyzed genome-wide key regulatory genes for micro-metabolites, combined with fermented cherry juice flavor metabolomics data, and used machine learning to explore correlations between gene regulation, metabolite production, and flavor formation. The SVM model screened and verified fermented cherry juice VOCs; through OAV and flavor wheel analysis, LD1.0600 emerged as the top-performing strain, with a sweet, fruity dominant aroma. Key aroma-active components (OAV > 100) included 2-methoxy-4-vinylphenol, benzaldehyde, 2-methyl-butanoic acid and hexanoic acid, and 2-methoxy-4-vinylphenol and hexanoic acid elevated by LD1.0600-regulated genes (Chrom1-001884, Chrom1-000925, fabF and Chrom1-000199). At the same time, through research, a "strain screening-SVM screening of DVCs-OAV screening of key aroma components-whole genome sequencing of flavor regulatory genes" system was established. This system can not only be applied to the screen fermentation strains, but also can be extended to the application of other fermentation products.

Fermentation

Whole-genome analysis of Brevibacterium sanguinis AZMABM HM27: a bacterial isolate from the sea anemone Radianthus magnifica and exhibiting promising multi-therapeutic properties.

BACKGROUND: The marine anemone Radianthus magnifica harbors symbiotic microbes with promising biomedical potential, yet their diversity and therapeutic properties remain underexplored. This study aimed to characterize a symbiotic bacterium isolated from R. magnifica collected from Samalona Island, Indonesia, and to evaluate its multi-therapeutic potential. METHODS: Strain AZMABM HM27 was characterized using whole-genome sequencing, functional annotation, biosynthetic gene cluster prediction, molecular docking, and in vitro bioactivity assays. RESULTS: Phylogenetic and genome-based analyses confirmed AZMABM HM27 as Brevibacterium sanguinis, with an OrthoANI value of 97.37% and a dDDH value of 76.50% against the type strain. The genome comprises a 3,834,082 bp chromosome encoding 3,362 protein-coding genes, including 95 genes involved in secondary metabolite biosynthesis. Five biosynthetic gene clusters were predicted, including those associated with ectoine, terpene, and siderophore production. The crude extract demonstrated antioxidant activity (IC₅₀ = 0.87 mg/mL), anti-inflammatory activity (up to 60% inhibition), antidiabetic activity through α-glucosidase inhibition (up to 40% inhibition), and dose-dependent antiproliferative activity against MCF-7 breast cancer cells (74.10% viability at 1 mg/mL). Molecular docking identified a lead compound, 8,9,9,10,10,11-hexafluoro-4,4-dimethyl-3,5-dioxatetracyclo [5.4.1.0(2,6)0.0(8,11)] dodecane, with strong binding affinities to selected therapeutic targets. CONCLUSIONS: B. sanguinis AZMABM HM27 represents a marine symbiotic strain associated with R. magnifica and a promising source of bioactive compounds with antioxidant, anti-inflammatory, antidiabetic, and antiproliferative potential. Further purification, structural elucidation, and in vivo studies are warranted to validate its therapeutic potential.

Animals

Whole-Genome Analysis of Multidrug-Resistant Escherichia coli from Bloodstream Infections in Iraqi Cancer Patients.

BACKGROUND: In Iraq, oncology patients with bloodstream infections face escalating treatment challenges due to rising antimicrobial resistance in Escherichia coli, compounded by limited diagnostic capacity and restricted therapeutic options. However, data from oncology settings in Iraq are limited. This study aimed to characterize and compare the antimicrobial resistance gene profiles of multidrug-resistant and antibiotic-sensitive E. coli isolates from cancer patients, to inform infection control and stewardship strategies. METHODS: A prospective, multicenter investigation was conducted in three oncology hospitals in Baghdad. Fifty-five Escherichia coli bloodstream isolates, 36 multidrug-resistant (MDR) (65.5%) and 19 antibiotic-sensitive (34.5%), underwent phenotypic susceptibility testing using VITEK® 2 and disk diffusion. Whole-genome sequencing (Illumina MiSeq) was performed, and antimicrobial resistance genes (ARGs) were identified using AMRFinderPlus and classified by functional category. RESULTS: MDR isolates showed a broad resistome dominated by efflux systems. Across all isolates, a total of 36 unique antimicrobial resistance genes were identified, underscoring substantial resistome diversity., efflux pump genes were detected in 100%, β-lactamase genes in 88.9%, macrolide resistance genes in 66.7%, tetracycline resistance genes in 55.6%, and aminoglycoside resistance genes in 41.7%. Representative determinants included AcrAB-TolC/EmrAB-TolC/MdtABC-TolC (efflux) and BlaEC family/CMY-42/TEM types (β-lactams). Among sensitive isolates, only 11 antibiotic-associated genes, mainly efflux or regulators (e.g., acrF, emrD, emrR, emrY, tolC; regulators marR, evgA; target parC; others baeS, cpxA, cysB), overlapped with MDR, suggesting a shared core that is insufficient alone for phenotypic resistance without additional high-level mechanisms. CONCLUSIONS: Multidrug-resistant E. coli from oncology patients harbor dense, efflux-driven resistomes supplemented by diverse β-lactamases and other resistance determinants, while sensitive isolates retain a limited core set of genes. Genomic surveillance in cancer centers is critical for anticipating resistance emergence and informing targeted antimicrobial strategies.

Humans

Whole-Genome Analysis of HEV Under Sequential Ribavirin Pressure Reveals Early Minor Variants Predicting Resistance.

Ribavirin (RBV) failures in chronic hepatitis E virus (HEV) infection may arise from genomic adaptation, yet the contribution of minor variants remains insufficiently explored. Using a shotgun metagenomics based on next-generation sequencing to obtain the full HEV genome, we analyzed longitudinal HEV populations from sequential clinical samples collected from a patient infected by Paslahepevirus balayani genotype 3c, who underwent three different courses of RBV treatment. Viral diversity increased over time, with most amino-acid substitutions detected at sub-consensus frequencies. Several mutations linked to RBV resistance emerged under treatment pressure. Specifically, D1384N and Y1587F became fixed in the final sampling, while additional substitutions at position 1384 (including D1384T) revealed mutational hotspot. Importantly, D1384N and G1634R were already detectable at low allele frequencies after the first treatment cessation and subsequent rebound, showing that the study of minor variant populations can be early predictors for the development of RBV resistance. These findings underscore the genomic plasticity of HEV under antiviral pressure and highlight the value of deep variant profiling for anticipating RBV treatment failure.

Ribavirin

Whole genome sequence analysis of low-density lipoprotein cholesterol across 246 K individuals.

BACKGROUND: Rare genetic variation provided by whole genome sequence datasets has been relatively less explored for its contributions to human traits. Meta-analysis of sequencing data offers advantages by integrating larger sample sizes from diverse cohorts, thereby increasing the likelihood of discovering novel insights into complex traits. Furthermore, emerging methods in genome-wide rare variant association testing further improve power and interpretability. RESULTS: Here, we conduct the largest meta-analysis of whole genome sequencing for low-density lipoprotein cholesterol (LDL-C), a therapeutic target for coronary artery disease, analyzing data from 246 K participants and integrating 1.23B variants from the UK Biobank and the Trans-Omics for Precision Medicine (TOPMed) program. We identify numerous rare coding and non-coding gene associations related to LDL-C, with replication across 86 K participants in All of Us. Our findings are based on single-variant analyses, rare coding and non-coding variant aggregation tests, and sliding window approaches. Through this comprehensive analysis, we identify 704 novel single-variant associations, 25 novel rare coding variant aggregates, 28 novel rare non-coding variant aggregates, and one novel sliding window aggregate. CONCLUSIONS: This study provides a meta-analysis framework for large-scale whole genome sequence association analyses from diverse population groups, yielding novel rare non-coding variant associations.

Humans

Whole Genome Methylation Sequencing via Enzymatic Conversion (EM-seq): Protocol, Data Processing, and Analysis.

Whole genome bisulfite sequencing (WGBS) has been the gold standard technique for base resolution analysis of DNA methylation for the last 15 years. It has been, however, associated with technical biases, which lead to overall overestimation of global and regional methylation values, and significant artifacts in extreme cytosine-rich DNA sequence contexts. Enzymatic conversion of cytosine is the newest approach, set to replace entirely the use of the damaging bisulfite conversion of DNA. The EM-seq technique utilizes TET2, T4-BGT, and APOBEC in a two-step conversion process, where the modified cytosines are first protected by oxidation and glucosylation, followed by deamination of all unmodified cytosines to uracil. As a result, EM-seq is degradation-free and bias-free, requires low DNA input, and produces high library yields with longer reads, little batch variation, less duplication, uniform genomic coverage, accurate methylation over a larger number of captured CpGs, and no sequence-specific artifacts.

DNA Methylation

The impact of the COVID-19 pandemic on the incidence of invasive pneumococcal disease in the Czech Republic and whole genome sequencing analysis of Streptococcus pneumoniae serotypes 3 and 19A from 2018-2024.

AIM: To describe in detail changes in the incidence of invasive pneumococcal disease in the Czech Republic during and after the COVID-19 pandemic. Another objective is molecular analysis of S. pneumoniae isolates of serotypes 3 and 19A recovered in the Czech Republic between 2018 and 2024. MATERIAL AND METHODS: Data on the incidence of invasive pneumococcal disease and S. pneumoniae serotypes were obtained from the invasive pneumococcal disease surveillance program in the Czech Republic. S. pneumoniae isolates of serotypes 3 (63) and 19A (66) from 2018-2024 were subjected to whole genome sequencing (WGS) to characterize the GPSCs (Global Pneumococcal Sequence Clusters) and STs (sequence types) and place them in a global context. RESULTS: Results: During the COVID-19 pandemic, a significant decline was observed in the incidence of invasive pneumococcal disease in the Czech Republic. Following the pandemic, the incidence of invasive pneumococcal disease rose again to significantly higher levels than before the pandemic. Compared to the 2018–2019 period, the incidence of certain serotypes increased in 2023–2024, including vaccine serotypes 3, 4, 14, and 15B, while the incidence of serotypes 8, 12F, and 15A, among others, decreased. Whole genome sequencing analysis demonstrated the dominance of GPSC12 ST-180 among serotype 3 isolates throughout the study period. Among serotype 19A isolates, GPSC4 prevailed, particularly ST-416. CONCLUSIONS: The COVID-19 pandemic has demonstrated how rapidly the epidemiological situation of invasive pneumococcal disease can change and that continuous, systematic surveillance of invasive pneumococcal disease is necessary. The best prevention against invasive pneumococcal disease is vaccination, primarily with higher valency pneumococcal conjugate vaccines.

Czech Republic

Evaluating 12 automated, whole-genome sequencing analysis pipelines for Mycobacterium tuberculosis complex: a comparative study.

BACKGROUND: Reliance on complex, custom-built bioinformatics pipelines is a barrier to the implementation of whole-genome sequencing (WGS) of Mycobacterium tuberculosis in high-burden settings in some low-income and middle-income countries (LMICs). Automated analysis pipelines could address this inequity in access to WGS-based diagnostics and surveillance. This study aimed to systematically evaluate the performance and usability of publicly available WGS pipelines for M tuberculosis. METHODS: We identified automated M tuberculosis WGS analysis pipelines through searches of PubMed and GitHub from database inception up to Aug 31, 2024. Accuracy, cost, accessibility, and scalability were assessed for each pipeline. We evaluated the accuracy of genotypic drug susceptibility testing (gDST) using publicly available sequences with phenotypic susceptibility data for 12 antituberculosis drugs. We estimated pooled sensitivity and specificity for each pipeline, across all drugs, by conducting a bivariate meta-analysis, with random effects representing between-drug variability. Lineage classifications were compared, and a previously epidemiologically well-characterised dataset was used to compare measures of genomic relatedness. FINDINGS: Among 28 candidate pipelines, 16 were excluded as they were unmaintained and inexecutable. 12 pipelines (11 compatible with Illumina and four compatible with Nanopore), all free to use, were included for evaluation. Six pipelines processed and stored data remotely, but for five of these six, scalability was limited by the need to upload sequences through web portals. For local processing pipelines, scalability was dependent on substantial local computational resources, data storage capacity, and command-line interfaces that limited user-friendliness. Only one of six remote-processing pipelines removed human DNA sequences before server upload. gDST was similarly accurate across ten of 11 Illumina-compatible pipelines and three of four Nanopore-compatible pipelines. All pipelines classified the main lineages consistently, although there were differences at sublineage resolution. Outputs from three of four pipelines reporting genomic relatedness were compatible with commonly cited single nucleotide polymorphism difference thresholds. INTERPRETATION: Numerous automated analysis pipelines capable of enhancing equity in M tuberculosis WGS are available. Given the overall similarities between the pipelines evaluated in this study in terms of gDST performance, lineage classification, and genomic relatedness inference, non-functional attributes such as availability, accessibility, scalability, and privacy could represent the point of difference for prospective users in LMICs with a high burden of tuberculosis. FUNDING: The Rhodes Trust, Wellcome, Ellison Institute of Technology, and the UK National Institute for Health and Care Research Oxford Biomedical Research Centre.

Mycobacterium tuberculosis

Whole -genome survival analysis of 144 286 people from the UK Biobank identifies novel loci associated with blood pressure.

This study utilized UK Biobank data from 144 286 participants and employed whole-genome sequencing (WGS) data and time-to-event data over a 12-year follow-up period to identify susceptibility in genetic variants associated with hypertension. Following genotype quality control, 6 319 822 single nucleotide polymorphisms underwent analysis, revealing 31 significant variant-level associations. Among these, 29 were novel - 15 in Fibrillin-2 ( FBN2 ) and 4 in Junctophilin-2 ( JPH2 ). Mendelian randomization utilizing two identified variants (rs17677724 and rs1014754) suggested that a genetically induced decrease in heart FBN2 expression and an increase in adrenal gland JPH2 expression were causally linked to hypertension. Phenome-wide association (PheWAS) analysis using the FinnGen dataset confirmed positive associations of rs17677724 and rs1014754 with hypertension, assessed across 2727 traits in 377 277 individuals. Lastly, rs1014754 positively associated with kallistatin, whereas rs17677724 negatively associated with renin in the Fenland study, suggesting a counterregulatory response to high blood pressure. This study, employing WGS data, identified novel genetic loci and potential therapeutic targets for hypertension.

Humans

Whole-genome Sequence Analysis Revealed Novel Subjective Cognitive Decline-associated Genes in 10,763 Chinese.

Subjective cognitive decline (SCD) is widely regarded as a potential preclinical stage of Alzheimer's disease (AD), yet its genetic basis remains poorly understood. To address this gap, we investigated genetic biomarkers associated with SCD using whole-genome sequencing (WGS) in 10,763 Chinese participants from the Healthy Zhejiang One Million People Cohort (HOPE Cohort). The discovery stage included 9284 samples, with 1479 samples used for validation. Using a two-stage design, we systematically investigated both common and rare variants associated with SCD. In rare variant analyses, we identified and replicated an association between the upstream region of SEPHS2 and SCD. SEPHS2 is involved in selenophosphate synthesis, and a Mendelian randomization analysis reveals that its expression levels in both blood and brain cerebellum are associated with AD. Additionally, we identified CLVS2, which encodes a protein primarily expressed in neuronal cells, as a potential regulator for SCD based on missense rare variants. Multi-omics evidence suggests that both SEPHS2 and CLVS2 may play roles in neurodegenerative diseases. For common variants, we validated 8 known loci related to cognitive decline, 3 of which originated from the only existing SCD genetic study conducted under a migraine background. Overall, our WGS-based study fills the gap in SCD research by providing vital genetic evidence from an East Asian population and offers insights into the pathogenic mechanisms of SCD.

Aged

Whole genome sequencing analysis of Candida glabrata isolates collected from patients with selected drug-resistant candidiasis hospitalized in Eastern Poland.

The epidemiology data for candidiasis indicate an increase in Candida glabrata infections. Moreover, several reports have shown an increasing number of drug-resistant cases of these infections. The source of drug resistance can often be traced to genetic mutations in genes related to a drug's mechanism of action. Therefore, we conducted whole genome sequencing of several drug-resistant isolates of Candida glabrata collected from patients hospitalized in Eastern Poland to assess whether mutations in selected genes correlated with susceptibility analysis results. The fungal species from patient samples were identified, and the isolated Candida glabrata were subjected to antifungal drug susceptibility testing. The results were interpreted according to the EUCAST and CLSI recommendations. Susceptibility to 5-flucytosine was assessed using the ATB FUNGUS kit. Libraries were prepared according to the NEXTERA XT DNA Library Prep and subsequently sequenced. The outcomes indicated common resistance to two of the three analyzed echinocandins, as well as two cases of simultaneous resistance to echinocandins and selected azole-based drugs. We detected several previously reported mutations in selected resistance-related genes, as well as five that are first described here: ERG5 (M267I), ERG6 (R57K), PDH1 (K438Q, V434I, F600V, V1192S), FCY1 (M129T), and FCY2 (I384F). Neither of the identified nonsynonymous mutations was correlated with the drug resistance demonstrated in the susceptibility testing. Furthermore, we can exclude the possibility of acquired drug resistance, thereby raising questions about the possibility of unknown mechanisms of resistance to azole-based and echinocandin drugs.

Candida glabrata

Whole genome sequencing analysis and functional characterization of Lacticaseibacillus rhamnosus HP-B1083.

Lacticaseibacillus rhamnosus is an important strain for the biotransformation of natural products, and its crude extract exhibits biotransformation effect on glycosidic compounds such as baicalin. To further explore the potential of this strain, particularly given its previously demonstrated high-efficiency β-glucuronidase activity for baicalin conversion, whole-genome sequencing and functional annotation of Lacticaseibacillus rhamnosus HP-B1083 were performed in this study, and its acid tolerance, bile salt tolerance, short-term heat resistance and antibacterial activity were evaluated. The results showed that the strain possessed a circular chromosome with a full length of 3,090,505 bp and a GC content of 46.69%. Gene annotation revealed that the genome contained 2941 coding sequences (CDS) and 112 non-coding RNA genes, including 60 tRNA genes, 1 tmRNA gene, 36 misc_RNA genes and 15 rRNA genes. The functional annotations further reveal that this genome is rich in genes related to carbohydrate metabolism, hydrolases, and transferases, which is highly consistent with its phenotypic characteristics in glycoside transformation and the synthesis of antibacterial substances. In addition, acid tolerance, bile salt tolerance and short-term heat resistance experiments verified that HP-B1083 had acid resistance, bile salt resistance and short-term heat resistance. Antibacterial activity tests confirmed that HP-B1083 produced inhibition zone diameters over 10 mm against common foodborne pathogenic bacteria such as Escherichia coli and Bacillus cereus. Therefore, Lacticaseibacillus rhamnosus HP-B1083 has important application prospects in the development of functional foods, preparation of enzyme preparations and pharmaceutical industry.

Whole Genome Sequencing

Transmission of extended spectrum β-lactamase-producing Escherichia coli and antimicrobial resistance gene flow across One Health compartments in eastern Africa: a whole-genome sequence analysis from a prospective cohort study.

BACKGROUND: The One Health paradigm considers interdependence of human, animal, and environmental health. However, there is little evidence from high-income countries to support the importance of a One Health approach to addressing spread of antimicrobial resistance (AMR). Given AMR is a global threat, understanding how the close interactions of humans with animals and the environment in low-income settings affect the spread of AMR is important. We aimed to investigate diversity and transmission of extended spectrum β-lactamase (ESBL)-producing Escherichia coli across household-linked One Health compartments using genomic data. METHODS: We sequenced whole genomes of ESBL-producing E coli isolates from humans, animals, and the environment from a prospective, longitudinal cohort study conducted in Malawi (April 29, 2019, to Dec 3, 2020) and Uganda (July 16, 2020, to Aug 6, 2021). In the cohort study, 259 households were enrolled at baseline in Malawi and 92 in Uganda from a mix of urban, peri-urban, and rural areas. Households were followed up at months 1, 3, and 6 in Malawi and at months 1, 2, and 4 in Uganda. Samples collected at each visit included human and animal stool, environmental samples from hand-contact areas, food, and water, and broader environmental samples such as river water. Samples were cultured in buffered peptone water and then ESBL chromogenic agar to isolate ESBL-producing E coli. ESBL-producing E coli isolates underwent whole-genome sequencing. We performed phylogenetic analyses, and in-silico multi-locus sequence typing, characterised AMR determinants and linked genotypes with sample location, ecological source, and other covariates. We performed fine-scale single nucleotide polymorphism (SNP) and network analysis to infer strain and plasmid transmission across ecological compartments. The primary outcome was colonisation with ESBL-producing E coli. Secondary outcomes were genomic clusters and ESBL genomic determinants within and between One Health compartments. FINDINGS: We found high diversity of ESBL-producing E coli, with 170 sequence types and 166 genomic clusters identified from 2344 genomes, including 1814 genomes from Malawi (907 human, 221 animal, and 686 environmental) and 530 genomes from Uganda (380 human, 147 animal, and three environmental). Sequence type (ST)131 dominated in Malawi (209 [11·5%] of 1814 genomes), and ST10 dominated in Uganda (45 [8·5%] of 530 genomes). Common ESBL genes blaCTX-M-15 (1604 [68·4%] of 2344 genomes) and blaCTX-M-27 (336 [14·3%] of 2344 genomes) were carried on a complex network of 55 and 30 different plasmids. This diversity of plasmids presented multiple pathways for dissemination and revealed high force of selection. Phylogenetic analyses revealed common intermixing of isolates between humans, animals, and the environment. SNP transmission analysis revealed ecologically overlapping clusters, suggesting ESBL-producing E coli co-circulation both within and between compartments with frequent spillover events. Applying a five-SNP threshold, we inferred 463 human-environment transmission events, 146 human-animal events, and 142 animal-environment events. INTERPRETATION: Our work suggests that a One Health approach is crucial to addressing AMR in eastern Africa. Improving water, sanitation, and hygiene systems will create a safer environment, reduce spillovers of AMR bacteria between compartments, and eventually reduce AMR reservoirs in the environment and in animals. FUNDING: Medical Research Council, National Institute for Health and Care Research, and Wellcome Trust.

Humans