Establishment of a suspension array for Pseudomonas aeruginosa O-antigen serotyping.

Abstract Pseudomonas aeruginosa (P. aeruginosa) is widespread in the environment. It readily infects hospital and immunocompromised patients. Traditional biochemical and immunological diagnoses of P. aeruginosa infection cannot meet clinical demands. The variability of O-antigens is the primary basis for the serotyping schemes of many gram-negative bacteria, which is the most widely used method for pathogenic epidemiological purposes. In this study, we developed a suspension array that can accurately diagnose and identify 19 different P. aeruginosa O-antigen serotypes except O15, whose O-antigen gene cluster has not been characterized. In this assay, wzx / wzy genes were selected as the sero-specific gene for 18 serotypes other than O6, for which the glycosyltransferase gene wbpP was utilized. Meanwhile, the wzy β gene was added to separate O2/16 from O5/18/20, and the insertion sequence (IS) in wzx was used to separate O17 from O11. Eighty-two clinical isolates were screened to test our assay. A total of 65 isolates (79.3%) could be serotyped, and the result were confirmed to be correct by sequencing. Sensitivity analysis indicated that at least 5 ng DNA or 103 CFU cells could be detected using our suspension array. To our knowledge, this is the first report on serotyping P. aeruginosa by suspension array and may be of great value in the clinical diagnostics of P. aeruginosa infection. Highlights • Suspension array for P. aeruginosa O-antigen serotyping was constructed. • wzx/wzy were chosen for specific target genes. • This method was of high specificity and sensitivity. • This method can be used for P. aeruginosa clinical isolate serotyping. [ABSTRACT FROM AUTHOR]