Detection of Burkholderia pseudomallei O-antigen serotypes in near-neighbor species

Joshua K Stone,Stacey M Broomall,Bart J Currie,Lauren A Mcnew,Stephanie A Grasso,Mark Mayo,Adina Doyle,Henry S Gibbons,Shalamar Georgia,Stephanie D Warrington,Mark A Karavis,Christopher J Allender,Joseph M Insalaco,Apichai Tuanyok,Jennifer L Ginther,Paul Keim,Mirjam Kaestli,Kyle S Hubbard

doi:10.1186/1471-2180-12-250

Joshua K Stone, Stacey M Broomall + Show 16 more

Open Access

https://doi.org/10.1186/1471-2180-12-250

Copy DOI

Abstract

BackgroundBurkholderia pseudomallei is the etiological agent of melioidosis and a CDC category B select agent with no available effective vaccine. Previous immunizations in mice have utilized the lipopolysaccharide (LPS) as a potential vaccine target because it is known as one of the most important antigenic epitopes in B. pseudomallei. Complicating this strategy are the four different B. pseudomallei LPS O-antigen types: A, B, B2, and rough. Sero-crossreactivity is common among O-antigens of Burkholderia species. Here, we identified the presence of multiple B. pseudomallei O-antigen types and sero-crossreactivity in its near-neighbor species.ResultsPCR screening of O-antigen biosynthesis genes, phenotypic characterization using SDS-PAGE, and immunoblot analysis showed that majority of B. mallei and B. thailandensis strains contained the typical O-antigen type A. In contrast, most of B. ubonensis and B. thailandensis-like strains expressed the atypical O-antigen types B and B2, respectively. Most B. oklahomensis strains expressed a distinct and non-seroreactive O-antigen type, except strain E0147 which expressed O-antigen type A. O-antigen type B2 was also detected in B. thailandensis 82172, B. ubonensis MSMB108, and Burkholderia sp. MSMB175. Interestingly, B. thailandensis-like MSMB43 contained a novel serotype B positive O-antigen.ConclusionsThis study expands the number of species which express B. pseudomallei O-antigen types. Further work is required to elucidate the full structures and how closely these are to the B. pseudomallei O-antigens, which will ultimately determine the efficacy of the near-neighbor B serotypes for vaccine development.

Highlights

Burkholderia pseudomallei is the etiological agent of melioidosis and a CDC category B select agent with no available effective vaccine
Further work is required to elucidate the full structures and how closely these are to the B. pseudomallei O-antigens, which will determine the efficacy of the near-neighbor B serotypes for vaccine development
B. thailandensis-like species is a new species within the Pseudomallei phylogenetic group which is closely related to B. pseudomallei and B. thailandensis

Summary

Introduction

Burkholderia pseudomallei is the etiological agent of melioidosis and a CDC category B select agent with no available effective vaccine. Previous immunizations in mice have utilized the lipopolysaccharide (LPS) as a potential vaccine target because it is known as one of the most important antigenic epitopes in B. pseudomallei. Complicating this strategy are the four different B. pseudomallei LPS O-antigen types: A, B, B2, and rough. Burkholderia pseudomallei is a saprophytic Gramnegative bacterium endemic to Southeast Asia and Australia It is the etiological agent of the septicemic disease melioidosis and a CDC category B select agent with no available effective vaccine [5,6]. The presence of types A and B2 in near-neighbor species suggests that further screening will reveal additional species expressing B. pseudomallei O-antigen types

Methods

Results

Discussion

Conclusion