O-Antigen Gene Clusters of Plesiomonas shigelloides Serogroups and Its Application in Development of a Molecular Serotyping Scheme

Abstract

Plesiomonas shigelloides is a Gram-negative, flagellated, rod-shaped, ubiquitous, and facultative anaerobic bacterium. It has been isolated from various sources, such as freshwater, surface water, and many wild and domestic animals. P. shigelloides is associated with diarrheal diseases of acute secretory gastroenteritis, an invasive shigellosis-like disease, and a cholera-like illness in humans. At present, 102 somatic antigens and 51 flagellar antigens of P. shigelloides have been recognized; however, very little is known about variations of O-antigens among P. shigelloides species. In this study, 12 O-antigen gene clusters of P. shigelloides , O2H1a1c (G5877), O10H41 (G5892), O12H35 (G5890), O23H1a1c (G5263), O25H3 (G5879), O26H1a1c (G5889), O32H37 (G5880), O33H38 (G5881), O34H34 (G5882), O66H3 (G5270), O75H34 (G5885), and O76H39 (G5886), were sequenced and analyzed. The genes that control O-antigen synthesis are present as chromosomal gene clusters that maps between rep and aqpZ , and most of the synthesis and translocation of OPS (O-specific polysaccharide) belongs to Wzx/Wzy pathway with the exception of O12, O25, and O66, which use the ATP-binding cassette (ABC) transporter pathway. Phylogenetic analysis of wzx and wzy show that the wzx and wzy genes are specific to individual O-antigens and can be used as targets in molecular typing. Based on the sequence data, an O-antigen specific suspension array that detects 12 distinct OPS’ has been developed. This is the first report to catalog the genetic features of P. shigelloides O-antigen variations and develop a suspension array for the molecular typing. The method has several advantages over traditional bacteriophage and serum agglutination methods and lays the foundation for easier identification and detection of additional O-antigen in the future.

Genetic loci of theR. anatipestiferserotype discovered by Pan-GWAS and its application for the development of a multiplex PCR serotyping method

“…The comparison of the O-AGCs of a total of 11 serotypes indicates that the O-AGC of R. anatipestifer is conserved at both ends and variable in the middle region (Figure 8). Similar phenomena also appeared in Plesiomonas shigelloides (Xi et al, 2019), Escherichia albertii (Wang et al, 2017b), and Yersinia pseudotuberculosis (Kenyon et al, 2017). Variations in the O-AGCs often mean differences in the O-antigen oligosaccharide unit and affect the serological phenotype.…”

“…wzy , wzx etc.) have been widely used as targets for molecular serotyping of many gram-negative bacteria(Fang et al, 2016; Iguchi et al, 2020; Townsend et al, 2001; Wang et al, 2017a; Xi et al, 2019; Zeng et al, 2019).…”

Horizontal Gene Transfer Clarifies Taxonomic Confusion and Promotes the Genetic Diversity and Pathogenicity of Plesiomonas shigelloides

“…To better understand the genetic diversity and pathogenic potential of P. shigelloides , we generated draft genome sequences for 12 strains representing different serogroups whose O-antigen gene clusters have been reported previously ( 18 ). Phylogeny was performed for a larger collection of the members of Enterobacterales , focusing on the phylogenetic position of P. shigelloides and species-specific genetic properties.…”

Genetic Analysis and Serological Detection of Novel O-Antigen Gene Clusters of Plesiomonas shigelloides

“…P. shigelloides O17, which carries the same O-antigen as Shigella sonnei , was used in vaccine production against shigellosis [ 7 ]. Our previous study reported the diversity of P. shigelloides O-antigen gene clusters, and also established an identification and detection method for molecular serotyping [ 8 ]. The variability of the O-antigen provides the primary basis for serotyping schemes for P. shigelloides [ 9 ].…”