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PloS One 2024Typhoid fever, caused by Salmonella enterica serovar typhi, presents a substantial global health threat, particularly in regions with limited healthcare infrastructure....
Typhoid fever, caused by Salmonella enterica serovar typhi, presents a substantial global health threat, particularly in regions with limited healthcare infrastructure. The rise of multidrug-resistant strains of S. typhi exacerbates this challenge, severely compromising conventional treatment efficacy due to over activity of efflux pumps. In our study, a comprehensive exploration of two fundamental aspects to combat MDR in S. typhi is carried out; i.e. employing advanced bioinformatics analyses and AlphaFold AI, We successfully identified and characterised a putative homologue, ABC-TPA, reminiscent of the P-glycoprotein (P-gp) known for its role in multidrug resistance in diverse pathogens. This discovery provides a critical foundation for understanding the potential mechanisms driving antibiotic resistance in S. typhi. Furthermore, employing computational methodologies, We meticulously assessed the potential of lignans, specifically Schisandrin A, B, and C, as promising Efflux Pump Inhibitors (EPIs) against the identified P-gp homologue in S. typhi. Noteworthy findings revealed robust binding interactions of Schisandrin A and B with the target protein, indicating substantial inhibitory capabilities. In contrast, Schisandrin C exhibited instability, showing varied effectiveness among the evaluated lignans. Pharmacokinetics and toxicity predictions underscored the favourable attributes of Schisandrin A, including prolonged action duration. Furthermore, high systemic stability and demanished toxicity profile of SA and SB present their therapeutic efficacy against MDR. This comprehensive investigation not only elucidates potential therapeutic strategies against MDR strains of S. typhi but also highlights the relevance of computational approaches in identifying and evaluating promising candidates. These findings lay a robust foundation for future empirical studies to address the formidable challenges antibiotic resistance poses in this clinically significant infectious diseases.
Topics: Salmonella typhi; Drug Resistance, Multiple, Bacterial; Lignans; Anti-Bacterial Agents; Bacterial Proteins; Humans; Microbial Sensitivity Tests; Computational Biology
PubMed: 38917154
DOI: 10.1371/journal.pone.0303285 -
Microbiology (Reading, England) Jun 2024Metagenome community analyses, driven by the continued development in sequencing technology, is rapidly providing insights in many aspects of microbiology and becoming a...
Metagenome community analyses, driven by the continued development in sequencing technology, is rapidly providing insights in many aspects of microbiology and becoming a cornerstone tool. Illumina, Oxford Nanopore Technologies (ONT) and Pacific Biosciences (PacBio) are the leading technologies, each with their own advantages and drawbacks. Illumina provides accurate reads at a low cost, but their length is too short to close bacterial genomes. Long reads overcome this limitation, but these technologies produce reads with lower accuracy (ONT) or with lower throughput (PacBio high-fidelity reads). In a critical first analysis step, reads are assembled to reconstruct genomes or individual genes within the community. However, to date, the performance of existing assemblers has never been challenged with a complex mock metagenome. Here, we evaluate the performance of current assemblers that use short, long or both read types on a complex mock metagenome consisting of 227 bacterial strains with varying degrees of relatedness. We show that many of the current assemblers are not suited to handle such a complex metagenome. In addition, hybrid assemblies do not fulfil their potential. We conclude that ONT reads assembled with CANU and Illumina reads assembled with SPAdes offer the best value for reconstructing genomes and individual genes of complex metagenomes, respectively.
Topics: Metagenome; Benchmarking; High-Throughput Nucleotide Sequencing; Metagenomics; Bacteria; Sequence Analysis, DNA; Genome, Bacterial; Microbiota
PubMed: 38916949
DOI: 10.1099/mic.0.001469 -
Emerging Infectious Diseases Jul 2024To determine antimicrobial susceptibility of Neisseria gonorrhoeae, we analyzed phenotypes and genomes of 72 isolates collected in Cambodia in 2023. Of those, 9/72...
To determine antimicrobial susceptibility of Neisseria gonorrhoeae, we analyzed phenotypes and genomes of 72 isolates collected in Cambodia in 2023. Of those, 9/72 (12.5%) were extensively drug resistant, a 3-fold increase from 2022. Genomic analysis confirmed expansion of newly emerging resistant clones and ongoing resistance emergence across new phylogenetic backbones.
Topics: Neisseria gonorrhoeae; Cambodia; Humans; Gonorrhea; Anti-Bacterial Agents; Microbial Sensitivity Tests; World Health Organization; Drug Resistance, Bacterial; Phylogeny; Male; Female; Adult
PubMed: 38916864
DOI: 10.3201/eid3007.240354 -
International Journal of... Apr 2024Tuberculosis (TB), a global infectious threat, has seen a concerning rise in aminoglycoside-resistant Mycobacterium tuberculosis (M.tb) strains. The potential role of... (Comparative Study)
Comparative Study
Comparative Proteomic Analysis of Capsule Proteins in Aminoglycoside-Resistant and Sensitive Mycobacterium tuberculosis Clinical Isolates: Unraveling Potential Drug Targets.
BACKGROUND
Tuberculosis (TB), a global infectious threat, has seen a concerning rise in aminoglycoside-resistant Mycobacterium tuberculosis (M.tb) strains. The potential role of capsule proteins remains largely unexplored. This layer acts as the primary barrier for tubercle bacilli, attempting to infiltrate host cells and subsequent disease development.
METHODS
The study aims to bridge this gap by investigating the differentially expressed capsule proteins in aminoglycoside-resistant M.tb clinical isolates compared with drug-sensitive isolates employing two-dimensional gel electrophoresis, mass spectrometry, and bioinformatic approaches.
RESULTS
We identified eight proteins that exhibited significant upregulation in aminoglycoside-resistant isolates. Protein Rv3029c and Rv2110c were associated with intermediary metabolism and respiration; Rv2462c with cell wall and cell processes; Rv3804c with lipid metabolism; Rv2416c and Rv2623 with virulence and detoxification/adaptation; Rv0020c with regulatory functions; and Rv0639 with information pathways. Notably, the Group-based Prediction System for Prokaryotic Ubiquitin-like Protein (GPS-PUP) algorithm identified potential pupylation sites within all proteins except Rv3804c. Interactome analysis using the STRING 12.0 database revealed potential interactive partners for these proteins, suggesting their involvement in aminoglycoside resistance. Molecular docking studies revealed suitable binding between amikacin and kanamycin drugs with Rv2462c, Rv3804c, and Rv2623 proteins.
CONCLUSION
As a result, our findings illustrate the multifaceted nature of aminoglycoside resistance in M.tb and the importance of understanding how capsule proteins play a role in counteracting drug efficacy. Identifying the role of these proteins in drug resistance is crucial for developing more effective treatments and diagnostics for TB.
Topics: Mycobacterium tuberculosis; Humans; Proteomics; Bacterial Proteins; Aminoglycosides; Drug Resistance, Bacterial; Bacterial Capsules; Antitubercular Agents; Microbial Sensitivity Tests; Computational Biology; Electrophoresis, Gel, Two-Dimensional; Tuberculosis
PubMed: 38916392
DOI: 10.4103/ijmy.ijmy_47_24 -
Microbiology Spectrum Jun 2024The incidence of heterogeneous vancomycin-intermediate (hVISA) infection is increasing and is associated with vancomycin treatment failures. However, studies...
The incidence of heterogeneous vancomycin-intermediate (hVISA) infection is increasing and is associated with vancomycin treatment failures. However, studies investigating the risk factors for treatment failure in hVISA infection are limited. Patients with hVISA bacteremia treated with vancomycin over 7 days between August 2008 and June 2020 were enrolled in this study. Clinical and microbiological characteristics were compared between vancomycin treatment failure and success groups to identify the risk factors for vancomycin treatment failure. Among the 180 patients with hVISA bacteremia, 102 patients treated with vancomycin over 7 days were included. Vancomycin treatment failed in 80 (78%) patients. Patients in the vancomycin treatment failure group were older ( < 0.001) and more frequently had solid cancer ( = 0.04) than those in the vancomycin treatment success group. Solid organ transplantation (SOT) was more frequent ( < 0.001) in the vancomycin treatment success group. The Charlson comorbidity index ( = 0.01) and Acute Physiology and Chronic Health Evaluation II scores ( < 0.001) were higher in the vancomycin treatment failure group. In multivariate analysis, independent risk factors for vancomycin treatment failure were old age and severity of bacteremia. SOT and vancomycin minimal inhibitory concentration (MIC) ≤ 1.0 mg/L using the broth microdilution (BMD) method were associated with successful vancomycin treatment. Old age and infection severity were independent risk factors for vancomycin treatment failure. Vancomycin MIC using the BMD method is an important risk factor for vancomycin treatment failure, and its use should be considered in hVISA bacteremia.IMPORTANCEIn this study, we assessed the clinical and microbiological characteristics of heterogeneous vancomycin-intermediated (hVISA) bacteremia and identified risk factors for vancomycin treatment failure. We found that advanced age and severity of infection were independent risk factors for vancomycin treatment failure. On the other hand, solid organ transplantation and a low vancomycin minimal inhibitory concentration were associated with successful vancomycin treatment. This study highlights the importance of vancomycin minimal inhibitory concentration in hVISA bacteremia.
PubMed: 38916352
DOI: 10.1128/spectrum.00333-24 -
Microbiology (Reading, England) Jun 2024Bacterial infection is a dynamic process resulting in a heterogenous population of infected and uninfected cells. These cells respond differently based on their...
Bacterial infection is a dynamic process resulting in a heterogenous population of infected and uninfected cells. These cells respond differently based on their bacterial load and duration of infection. In the case of infection of macrophages with Crohn's disease (CD) associated adherent-invasive (AIEC), understanding the drivers of pathogen success may allow targeting of cells where AIEC replicate to high levels. Here we show that stratifying immune cells based on their bacterial load identifies novel pathways and therapeutic targets not previously associated with AIEC when using a traditional homogeneous infected population approach. Using flow cytometry-based cell sorting we stratified cells into those with low or high intracellular pathogen loads, or those which were bystanders to infection. Immune cells transcriptomics revealed a diverse response to the varying levels of infection while pathway analysis identified novel intervention targets that were directly related to increasing intracellular AIEC numbers. Chemical inhibition of identified targets reduced AIEC intracellular replication or inhibited secretion of tumour necrosis factor alpha (TNFα), a key cytokine associated with AIEC infection. Our results have identified new avenues of intervention in AIEC infection that may also be applicable to CD through the repurposing of already available inhibitors. Additionally, they highlight the applicability of immune cell stratification post-infection as an effective approach for the study of microbial pathogens.
Topics: Crohn Disease; Macrophages; Humans; Escherichia coli Infections; Escherichia coli; Tumor Necrosis Factor-alpha; Bacterial Load; Bacterial Adhesion; Host-Pathogen Interactions
PubMed: 38916198
DOI: 10.1099/mic.0.001470 -
BioRxiv : the Preprint Server For... Jun 2024Pathological forms of the protein α-synuclein contribute to a family of disorders termed synucleinopathies, which includes Parkinson's disease (PD). Most cases of PD...
Pathological forms of the protein α-synuclein contribute to a family of disorders termed synucleinopathies, which includes Parkinson's disease (PD). Most cases of PD are believed to arise from gene-environment interactions. Microbiome composition is altered in PD, and gut bacteria are causal to symptoms and pathology in animal models. To explore how the microbiome may impact PD-associated genetic risks, we quantitatively profiled nearly 630 metabolites from 26 biochemical classes in the gut, plasma, and brain of α-synuclein-overexpressing (ASO) mice with or without microbiota. We observe tissue-specific changes driven by genotype, microbiome, and their interaction. Many differentially expressed metabolites in ASO mice are also dysregulated in human PD patients, including amine oxides, bile acids and indoles. Notably, levels of the microbial metabolite trimethylamine N-oxide (TMAO) strongly correlate from the gut to the plasma to the brain, identifying a product of gene-environment interactions that may influence PD-like outcomes in mice. TMAO is elevated in the blood and cerebral spinal fluid of PD patients. These findings uncover broad metabolomic changes that are influenced by the intersection of host genetics and the microbiome in a mouse model of PD.
PubMed: 38915679
DOI: 10.1101/2024.06.07.597975 -
Clinical Epigenetics Jun 2024Gastrointestinal malignancies encompass a diverse group of cancers that pose significant challenges to global health. The major histocompatibility complex (MHC) plays a... (Review)
Review
BACKGROUND
Gastrointestinal malignancies encompass a diverse group of cancers that pose significant challenges to global health. The major histocompatibility complex (MHC) plays a pivotal role in immune surveillance, orchestrating the recognition and elimination of tumor cells by the immune system. However, the intricate regulation of MHC gene expression is susceptible to dynamic epigenetic modification, which can influence functionality and pathological outcomes.
MAIN BODY
By understanding the epigenetic alterations that drive MHC downregulation, insights are gained into the molecular mechanisms underlying immune escape, tumor progression, and immunotherapy resistance. This systematic review examines the current literature on epigenetic mechanisms that contribute to MHC deregulation in esophageal, gastric, pancreatic, hepatic and colorectal malignancies. Potential clinical implications are discussed of targeting aberrant epigenetic modifications to restore MHC expression and 0 the effectiveness of immunotherapeutic interventions.
CONCLUSION
The integration of epigenetic-targeted therapies with immunotherapies holds great potential for improving clinical outcomes in patients with gastrointestinal malignancies and represents a compelling avenue for future research and therapeutic development.
Topics: Humans; Gastrointestinal Neoplasms; Epigenesis, Genetic; Major Histocompatibility Complex; Gene Expression Regulation, Neoplastic; Immunotherapy; DNA Methylation; Tumor Escape
PubMed: 38915093
DOI: 10.1186/s13148-024-01698-8 -
BMC Research Notes Jun 2024New characterized carbohydrate-active enzymes are needed for use as tools to discriminate complex carbohydrate structural features. Fungal glycoside hydrolase family 3...
OBJECTIVE
New characterized carbohydrate-active enzymes are needed for use as tools to discriminate complex carbohydrate structural features. Fungal glycoside hydrolase family 3 (GH3) β-xylosidases have been shown to be useful for the structural elucidation of glucuronic acid (GlcA) and arabinofuranose (Araf) substituted oligoxylosides. A homolog of these GH3 fungal enzymes from the bacterium Segatella baroniae (basonym Prevotella bryantii), Xyl3C, has been previously characterized, but those studies did not address important functional specificity features. In an interest to utilize this enzyme for laboratory methods intended to discriminate the structure of the non-reducing terminus of substituted xylooligosaccharides, we have further characterized this GH3 xylosidase.
RESULTS
In addition to verification of basic functional characteristics of this xylosidase we have determined its mode of action as it relates to non-reducing end xylose release from GlcA and Araf substituted oligoxylosides. Xyl3C cleaves xylose from the non-reducing terminus of β-1,4-xylan until occurrence of a penultimate substituted xylose. If this substitution is O2 linked, then Xyl3C removes the non-reducing xylose to leave the substituted xylose as the new non-reducing terminus. However, if the substitution is O3 linked, Xyl3C does not hydrolyze, thus leaving the substitution one-xylose (penultimate) from the non-reducing terminus. Hence, Xyl3C enables discrimination between O2 and O3 linked substitutions on the xylose penultimate to the non-reducing end. These findings are contrasted using a homologous enzyme also from S. baroniae, Xyl3B, which is found to yield a penultimate substituted nonreducing terminus regardless of which GlcA or Araf substitution exists.
Topics: Xylosidases; Xylans; Xylose; Substrate Specificity; Prevotella; Oligosaccharides; Glucuronates; Arabinose
PubMed: 38915023
DOI: 10.1186/s13104-024-06835-3 -
BMC Bioinformatics Jun 2024Pan-virus detection, and virome investigation in general, can be challenging, mainly due to the lack of universally conserved genetic elements in viruses. Metagenomic...
BACKGROUND
Pan-virus detection, and virome investigation in general, can be challenging, mainly due to the lack of universally conserved genetic elements in viruses. Metagenomic next-generation sequencing can offer a promising solution to this problem by providing an unbiased overview of the microbial community, enabling detection of any viruses without prior target selection. However, a major challenge in utilising metagenomic next-generation sequencing for virome investigation is that data analysis can be highly complex, involving numerous data processing steps.
RESULTS
Here, we present Entourage to address this challenge. Entourage enables short-read sequence assembly, viral sequence search with or without reference virus targets using contig-based approaches, and intrasample sequence variation quantification. Several workflows are implemented in Entourage to facilitate end-to-end virus sequence detection analysis through a single command line, from read cleaning, sequence assembly, to virus sequence searching. The results generated are comprehensive, allowing for thorough quality control, reliability assessment, and interpretation. We illustrate Entourage's utility as a streamlined workflow for virus detection by employing it to comprehensively search for target virus sequences and beyond in raw sequence read data generated from HeLa cell culture samples spiked with viruses. Furthermore, we showcase its flexibility and performance on a real-world dataset by analysing a preassembled Tara Oceans dataset. Overall, our results show that Entourage performs well even with low virus sequencing depth in single digits, and it can be used to discover novel viruses effectively. Additionally, by using sequence data generated from a patient with chronic SARS-CoV-2 infection, we demonstrate Entourage's capability to quantify virus intrasample genetic variations, and generate publication-quality figures illustrating the results.
CONCLUSIONS
Entourage is an all-in-one, versatile, and streamlined bioinformatics software for virome investigation, developed with a focus on ease of use. Entourage is available at https://codeberg.org/CENMIG/Entourage under the MIT license.
Topics: Software; Genome, Viral; Humans; High-Throughput Nucleotide Sequencing; SARS-CoV-2; Metagenomics; Viruses; COVID-19; Virome; HeLa Cells
PubMed: 38914932
DOI: 10.1186/s12859-024-05846-y