tailieunhanh - Báo cáo y học: "Genomic acquisition of a capsular polysaccharide virulence cluster by non-pathogenic Burkholderia isolates"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Wertheim cung cấp cho các bạn kiến thức về ngành y đề tài: Genomic acquisition of a capsular polysaccharide virulence cluster by non-pathogenic Burkholderia isolates. | Sim et al. Genome Biology 2010 11 R89 http 2010 11 8 R89 Genome Biology RESEARCH Open Access Genomie acquisition of a capsular polysaccharide virulence cluster by non-pathogenic Burkholderia isolates 1 1 1 4 Bernice Meng Qi Sim Narisara Chantratita Wen Fong Ooi Tannistha Nandi Ryan Tewhey Vanaporn Wuthiekanun3 Janjira Thaipadungpanit3 Sarinna Tumapa3 Pramila Ariyaratne1 Wing-Kin Sung1 5 Xiao Hui Sem1 Hui Hoon Chua1 Kalpana Ramnarayanan6 Chi Ho Lin1 Yichun Liu7 Edward J Feil8 Mindy B Glass9 Gladys Tan7 Sharon J Peacock2 10 Patrick Tan1 11 Abstract Background Burkholderia thailandensis is a non-pathogenic environmental saprophyte closely related to Burkholderia pseudomallei the causative agent of the often fatal animal and human disease melioidosis. To study B. thailandensis genomic variation we profiled 50 isolates using a pan-genome microarray comprising genomic elements from 28 Burkholderia strains and species. Results Of 39 genomic regions variably present across the B. thailandensis strains 13 regions corresponded to known genomic islands while 26 regions were novel. Variant B. thailandensis isolates exhibited isolated acquisition of a capsular polysaccharide biosynthesis gene cluster B. pseudomallei-like capsular polysaccharide closely resembling a similar cluster in B. pseudomallei that is essential for virulence in mammals presence of this cluster was confirmed by whole genome sequencing of a representative variant strain B. thailandensis E555 . Both wholegenome microarray and multi-locus sequence typing analysis revealed that the variant strains formed part of a phylogenetic subgroup distinct from the ancestral B. thailandensis population and were associated with atypical isolation sources when compared to the majority of previously described B. thailandensis strains. In functional assays B. thailandensis E555 exhibited several B. pseudomallei-like phenotypes including colony wrinkling resistance to human complement binding and .