Whole Genome Sequencing and Multiplex qPCR Methods to Identify Campylobacter jejuni Encoding cst-II or cst-III Sialyltransferase

Jason M Neal-McKinney, Kun C Liu, Karen C Jinneman, Wen-Hsin Wu, Daniel H Rice

Campylobacter jejuni causes more than 2 million cases of gastroenteritis annually in the United States, and is also linked to the autoimmune sequelae Guillan-Barre syndrome (GBS). GBS often results in flaccid paralysis, as the myelin sheaths of nerve cells are degraded by the adaptive immune response. Certain strains ofC. jejunimodify their lipooligosaccharide (LOS) with the addition of neuraminic acid, resulting in LOS moieties that are structurally similar to gangliosides present on nerve cells. This can trigger GBS in a susceptible host, as antibodies generated againstC. jejunican cross-react with gangliosides, leading to demyelination of nerves and a loss of signal transduction. The goal of this study was to develop a quantitative PCR (qPCR) method and use whole genome sequencing data to detect theCampylobactersialyltransferase (cst) genes responsible for the addition of neuraminic acid to LOS. The qPCR method was used to screen a library of 89C. jejunifield samples collected by the Food and Drug Administration Pacific Northwest Lab (PNL) as well as clinical isolates transferred to PNL.In silicoanalysis was used to screen 827C. jejunigenomes in the FDA GenomeTrakr SRA database. The results indicate that a majority ofC. jejunistrains could produce LOS with ganglioside mimicry, as 43.8% of PNL isolates and 46.9% of the GenomeTrakr isolates lacked thecstgenes. The methods described in this study can be used by public health laboratories to rapidly determine whether aC. jejuniisolate has the potential to induce GBS. Based on these results, a majority ofC. jejuniin the PNL collection and submitted to GenomeTrakr have the potential to produce LOS that mimics human gangliosides.