Amplicon identification using SparsE representation of multiplex PYROsequencing signal (AdvISER-M-PYRO): application to bacterial resistance genotyping.

Abstract

Pyrosequencing is a cost-effective DNA sequencing technology that has many applications, including rapid genotyping of a broad spectrum of bacteria. When molecular typing requires to genotype multiple DNA stretches, several pyrosequencing primers could be used simultaneously but this would create overlapping primer-specific signals, which are visually uninterpretable. Accordingly, the objective was to develop a new method for signal processing (AdvISER-M-PYRO) to automatically analyze and interpret multiplex pyrosequencing signals. In parallel, the nucleotide dispensation order was improved by developing the SENATOR ('SElecting the Nucleotide dispensATion Order') algorithm. In this proof-of-concept study, quintuplex pyrosequencing was applied on eight bacterial DNA and targeted genetic alterations underlying resistance to β-lactam antibiotics. Using SENATOR-driven dispensation order, all genetic variants (31 of 31; 100%) were correctly identified with AdvISER-M-PYRO. Among nine expected negative results, there was only one false positive that was tagged with an 'unsafe' label.