Defining the Genetic Features of O-Antigen Biosynthesis Gene Cluster and Performance of an O-Antigen Serotyping Scheme for .

is a newly described and emerging diarrheagenic pathogen responsible for outbreaks of gastroenteritis. Serotyping plays an important role in diagnosis and epidemiological studies for pathogens of public health importance. The diversity of O-antigen biosynthesis gene clusters (O-AGCs) provides the primary basis for serotyping. However, little is known about the distribution and diversity of O-AGCs of strains. Here, we presented a complete sequence set for the O-AGCs from 52 strains and identified seven distinct O-AGCs. Six of these were also found in 15 genomes of strains deposited in the public database. Possession of / genes in each O-AGC strongly suggest that O-antigens of were synthesized by the Wzx/Wzy-dependent pathway. Furthermore, we performed an O-antigen serotyping scheme for based on specific antisera against seven O-antigens and a high throughput xTAG Luminex assay to simultaneously detect seven O-AGCs. Both methods accurately identified serotypes of 64 tested strains. Our data revealed the high-level diversity of O-AGCs in . We also provide valuable methods to reliably identify and serotype this bacterium.