MOST: A modified MLST typing tool based on short read sequencing

Infectious Disease Informatics Unit, Public Health England, London, United Kingdom
Gastrointestinal Bacteria Reference Unit, Public Health England, London, United Kingdom
Respiratory and Vaccine Preventable Bacteria Reference Unit, Public Health England, London, United Kingdom
Antimicrobial Resistance and Healthcare Associated Infection unit, Public Health England, London, United Kingdom
DOI
10.7287/peerj.preprints.1971v1
Subject Areas
Bioinformatics, Microbiology
Keywords
whole genome sequencing, Multilocus sequence typing, mapping-based approach, assembly-based approach
Copyright
© 2016 Tewolde et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Tewolde R, Dallman T, Schaefer U, Sheppard CL, Ashton P, Pichon B, Ellington M, Swift C, Green J, Underwood A. 2016. MOST: A modified MLST typing tool based on short read sequencing. PeerJ Preprints 4:e1971v1

Abstract

Multilocus sequence typing (MLST) is an effective method to describe bacterial populations. Conventionally, MLST involves Polymerase Chain Reaction (PCR)amplification of housekeeping genes followed by Sanger DNA sequencing. Public Health England (PHE) is in the process of replacing the conventional MLST methodology with a method based on short read sequence data derived from Whole Genome Sequencing (WGS). This paper reports the comparison of the reliability of MLST results derived from WGS data, comparing mapping and assembly-based approaches to conventional methods using 325 bacterial genomes of diverse species. The sensitivity of the two WGS based methods were further investigated with 26 mixed and 29 low coverage genomic data sets from Salmonella enteridis and Streptococcus pneumoniae. Of the 325 samples, 92.9% (n=302), 97.2% (n=316) and 99.7% (n=324) full MLST profiles were derived by the conventional method, assembly- and mapping-based approaches, respectively. The concordance between samples that were typed by conventional (92.9%) and both WGS methods was 100%. From the 55 mixed and low coverage genomes, 90.9% (n=50) and 67.3% (n=37) full MLST profiles were derived from the mapping and assembly based approaches, respectively. In conclusion, deriving MLST from WGS data is more sensitive than the conventional method. When comparing WGS based methods, the mapping based approach was the most sensitive. In addition, the mapping based approach described here derives quality metrics, which are difficult to determine quantitatively using conventional and WGS-assembly based approaches.

Author Comment

This is a submission to PeerJ for review.

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