Biology subjects

Jason W Sahl

Publications and source records attributed to Jason W Sahl.

3 recordsLinked to original sources

bioRxiv2016

KlebSeq: A Diagnostic Tool for Healthcare Surveillance and Antimicrobial Resistance Monitoring of Klebsiella pneumoniae

Healthcare-acquired infections (HAIs) kill tens of thousands of people each year and add significantly to healthcare costs. Multidrug resistant and epidemic strains are a large proportion of HAI agents, and multidrug resistant strains of Klebsiella pneumoniae, a leading HAI agent, have become an urgent public health crisis. In the healthcare environment, patient colonization of K. pneumoniae precedes infection, and transmission via colonization leads to outbreaks. Periodic patient screening for K. pneumoniae colonization has cost-effective and life-saving potential. In this study, we describe the design and validation of KlebSeq, a highly informative screening tool that detects Klebsiella species and identifies clinically important strains and characteristics using highly multiplexed amplicon sequencing without a live culturing step. We demonstrate the utility of this tool on several complex specimen types including urine, wound swabs and tissue, several types of respiratory, and fecal, showing K. pneumoniae species and clonal group identification and antimicrobial resistance and virulence profiling, including capsule typing. Use of this amplicon sequencing tool can be used to screen patients for K. pneumoniae carriage to assess risk of infection and outbreak potential, and the expansion of this tool can be used for several other HAI agents or applications.

Molecular Biology↗

bioRxiv2016

The Northern Arizona SNP Pipeline (NASP): accurate, flexible, and rapid identification of SNPs in WGS datasets

Whole genome sequencing (WGS) of bacteria is becoming standard practice in many laboratories. Applications for WGS analysis include phylogeography and molecular epidemiology, using single nucleotide polymorphisms (SNPs) as the unit of evolution. The Northern Arizona SNP Pipeline (NASP) was developed as a reproducible pipeline that scales well with the large amount of WGS data typically used in comparative genomics applications. In this study, we demonstrate how NASP compares to other tools in the analysis of two real bacterial genomics datasets and one simulated dataset. Our results demonstrate that NASP produces comparable, and often better, results to other pipelines, but is much more flexible in terms of data input types, job management systems, diversity of supported tools, and output formats. We also demonstrate differences in results based on the choice of the reference genome and choice of inferring phylogenies from concatenated SNPs or alignments including monomorphic positions. NASP represents a source-available, version-controlled, unit-tested method and can be obtained from tgennorth.github.io/NASP.

Bioinformatics↗

bioRxiv2015

The In Silico Genotyper (ISG): an open-source pipeline to rapidly identify and annotate nucleotide variants for comparative genomics applications

The identification and annotation of nucleotide variants, including insertions/deletions and single nucleotide polymorphisms (SNPs), from whole genome sequence data is important for studies of bacterial evolution, comparative genomics, and phylogeography. The in Silico Genotyper (ISG) represents a parallel, tested, open source tool that can perform these functions and scales well to thousands of bacterial genomes. ISG is written in Java and requires MUMmer (Delcher, et al., 2003), BWA (Li and Durbin, 2009), and GATK (McKenna, et al., 2010) for full functionality. The source code and compiled binaries are freely available from https://github.com/TGenNorth/ISGPipeline under a GNU General Public License. Benchmark comparisons demonstrate that ISG is faster and more flexible than comparable tools.

Bioinformatics↗