Project description:<p>The study of antimicrobial resistance (AMR) in infectious diarrhea has generally been limited to cultivation, antimicrobial susceptibility testing and targeted PCR assays. When individual strains of significance are identified, whole genome shotgun (WGS) sequencing of important clones and clades is performed. Genes that encode resistance to antibiotics have been detected in environmental, insect, human and animal metagenomes and are known as "resistomes". While metagenomic datasets have been mined to characterize the healthy human gut resistome in the Human Microbiome Project and MetaHIT and in a Yanomani Amerindian cohort, directed metagenomic sequencing has not been used to examine the epidemiology of AMR. Especially in developing countries where sanitation is poor, diarrhea and enteric pathogens likely serve to disseminate antibiotic resistance elements of clinical significance. Unregulated use of antibiotics further exacerbates the problem by selection for acquisition of resistance. This is exemplified by recent reports of multiple antibiotic resistance in Shigella strains in India, in Escherichia coli in India and Pakistan, and in nontyphoidal Salmonella (NTS) in South-East Asia. We propose to use deep metagenomic sequencing and genome level assembly to study the epidemiology of AMR in stools of children suffering from diarrhea. Here the epidemiology component will be surveillance and analysis of the microbial composition (to the bacterial species/strain level where possible) and its constituent antimicrobial resistance genetic elements (such as plasmids, integrons, transposons and other mobile genetic elements, or MGEs) in samples from a cohort where diarrhea is prevalent and antibiotic exposure is endemic. The goal will be to assess whether consortia of specific mobile antimicrobial resistance elements associate with species/strains and whether their presence is enhanced or amplified in diarrheal microbiomes and in the presence of antibiotic exposure. This work could potentially identify clonal complexes of organisms and MGEs with enhanced resistance and the potential to transfer this resistance to other enteric pathogens.</p> <p>We have performed WGS, metagenomic assembly and gene/protein mapping to examine and characterize the types of AMR genes and transfer elements (transposons, integrons, bacteriophage, plasmids) and their distribution in bacterial species and strains assembled from DNA isolated from diarrheal and non-diarrheal stools. The samples were acquired from a cohort of pediatric patients and controls from Colombia, South America where antibiotic use is prevalent. As a control, the distribution and abundance of AMR genes can be compared to published studies where resistome gene lists from healthy cohort sequences were compiled. Our approach is more epidemiologic in nature, as we plan to identify and catalogue antimicrobial elements on MGEs capable of spread through a local population and further we will, where possible, link mobile antimicrobial resistance elements with specific strains within the population.</p>
| phs001260 | dbGaP
Project description:Strain-level identification of bacterial tomato pathogens directly from metagenomic sequences
Project description:Shotgun metagenomic sequencing of nasopharyngeal (NP) samples, from children enrolled in a PCV13-vaccinated South African birth cohort was used to explore strain-level pneumococcal colonization patterns and transmission dynamics, and associated antimicrobial-resistance determinants. NP swabs were collected at two-week intervals from birth through the first year of life from 137 infants. Pneumococcal isolates were serotyped and tested for phenotypic antimicrobial resistance. 196 NP samples from a subset of 23 infants were then selected based on changes in serotype or antimicrobial resistance. DNA was extracted directly from the enriched NP samples and shotgun metagenomic sequencing performed. Reads were assembled and aligned against reference pneumococcal genomes. in silico pneumococcal capsular, multilocus sequence typing, and resistome analyses were performed.
| EGAS00001004401 | EGA
Project description:Bacterial pathogens and antimicrobial resistance diagnosis workflow using Nanopore adaptive sampling method
Project description:Shotgun metagenomic sequencing data for nasopharyngeal colonization dynamics with Streptococcus pneumoniae and associated antimicrobial-resistance in a South African birth cohort.
Project description:Next-Generation-Sequencing (NGS) technologies have led to important improvement in the detection of new or unrecognized infective agents, related to infectious diseases. In this context, NGS high-throughput technology can be used to achieve a comprehensive and unbiased sequencing of the nucleic acids present in a clinical sample (i.e. tissues). Metagenomic shotgun sequencing has emerged as powerful high-throughput approaches to analyze and survey microbial composition in the field of infectious diseases. By directly sequencing millions of nucleic acid molecules in a sample and matching the sequences to those available in databases, pathogens of an infectious disease can be inferred. Despite the large amount of metagenomic shotgun data produced, there is a lack of a comprehensive and easy-use pipeline for data analysis that avoid annoying and complicated bioinformatics steps. Here we present HOME-BIO, a modular and exhaustive pipeline for analysis of biological entity estimation, specific designed for shotgun sequenced clinical samples. HOME-BIO analysis provides comprehensive taxonomy classification by querying different source database and carry out main steps in metagenomic investigation. HOME-BIO is a powerful tool in the hand of biologist without computational experience, which are focused on metagenomic analysis. Its easy-to-use intrinsic characteristic allows users to simply import raw sequenced reads file and obtain taxonomy profile of their samples.
Project description:Next-Generation-Sequencing (NGS) technologies have led to important improvement in the detection of new or unrecognized infective agents, related to infectious diseases. In this context, NGS high-throughput technology can be used to achieve a comprehensive and unbiased sequencing of the nucleic acids present in a clinical sample (i.e. tissues). Metagenomic shotgun sequencing has emerged as powerful high-throughput approaches to analyze and survey microbial composition in the field of infectious diseases. By directly sequencing millions of nucleic acid molecules in a sample and matching the sequences to those available in databases, pathogens of an infectious disease can be inferred. Despite the large amount of metagenomic shotgun data produced, there is a lack of a comprehensive and easy-use pipeline for data analysis that avoid annoying and complicated bioinformatics steps. Here we present HOME-BIO, a modular and exhaustive pipeline for analysis of biological entity estimation, specific designed for shotgun sequenced clinical samples. HOME-BIO analysis provides comprehensive taxonomy classification by querying different source database and carry out main steps in metagenomic investigation. HOME-BIO is a powerful tool in the hand of biologist without computational experience, which are focused on metagenomic analysis. Its easy-to-use intrinsic characteristic allows users to simply import raw sequenced reads file and obtain taxonomy profile of their samples.
Project description:Objectives: Therapies being safe, effective and not vulnerable to develop resistance are highly desirable to counteract bacterial infections. Host-directed therapeutics is an alternative to conventional antibiotics based on perturbing host pathways subverted by pathogens during their life cycle by the use of host-directed drugs to counteract microbial infections. This study sought to identify cellular genes and pathways differentially expressed during airways epithelial infection by nontypable Haemophilus influenzae (NTHi). NTHi is an opportunistic pathogen that is an important cause of exacerbation of chronic obstructive pulmonary disease (COPD). Based on the proposed relationship between NTHi intracellular location and persistence, the antimicrobial potential of a panel of drugs perturbing host pathways used by NTHi to enter epithelial cells was investigated. Methods: We screened for host genes differentially expressed upon infection by the clinical isolate NTHi375 by analyzing A549 cell whole genome expression profiling, and identified a panel of host target candidates which were pharmacologically modulated. Interfering drugs were tested for their bactericidal effect, cytotoxicity, effect on the interplay NTHi-epithelial cell, and effect on NTHi respiratory infection in vivo, by assessing lung bacterial loads in a murine intranasal infection model. Results: The sirtuin-1 activator resveratrol showed a bactericidal effect against NTHi; the PDE4 inhibitor rolipram showed therapeutic efficacy by lowering NTHi375 counts both intracellularly and in the lungs of infected mice. Conclusions: PDE4 inhibition is currently prescribed in COPD; resveratrol is a geroprotector attractive for COPD treatment by preventing lung aging. This work provides evidence for the antimicrobial potential of rolipram and resveratrol against NTHi respiratory infection. Haemophilus influenzae clinical strain NTHi375 induced gene expression in A549 human type II pneumocyte cell line was measured at 2 h post-infection. Non infected cells were used as a control. Four independent experiments were performed for each condition.