Genome-Wide Analysis Reveals Loci Encoding Anti-Macrophage Factors in the Human Pathogen Burkholderia pseudomallei K96243
Dowling, Andrea J.
Wilkinson, Paul A.
Holden, Matthew T. G.
Quail, Michael A.
Bentley, Stephen D.
Waterfield, Nicholas R.
Titball, Richard W.
ffrench-Constant, Richard H.
- Publisher: Public Library of Science
(issn: 1932-6203, eissn: 1932-6203)
Microbial Pathogens | Research Article | Corynebacterium-Pseudotuberculosis | Infectious Diseases | QR Microbiology | Virulence Plasmid | Functional Genomics | QH301 | Genomics | Macrophage Death | Host-Pathogen Interaction | QR | Syringae pv. Syringae | Plant Pathogen | Expression | Biology | Microbiology | QH426 | Medicine | Secretion System | Melioidosis | Burkholderia Infection | Bacterial Pathogens | Gram Negative | Phospholipase-D | QH426 Genetics | Bacterial Diseases | Q | Pathogenesis | R | Pertussis Filamentous Hemagglutinin | Science
This work was supported by the UK government under BBSRC grant BB/E021182/1 to R.H.ff-C and N.R.W. and by the European Community Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 223328 (GAMEXP) to R.H.ff-C and N.W. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Burkholderia pseudomallei is an important human pathogen whose infection biology is still poorly understood. The bacterium is endemic to tropical regions, including South East Asia and Northern Australia, where it causes melioidosis, a serious disease associated with both high mortality and antibiotic resistance. B. pseudomallei is a Gram-negative facultative intracellular pathogen that is able to replicate in macrophages. However despite the critical nature of its interaction with macrophages, few anti-macrophage factors have been characterized to date. Here we perform a genome-wide gain of function screen of B. pseudomallei strain K96243 to identify loci encoding factors with anti-macrophage activity. We identify a total of 113 such loci scattered across both chromosomes, with positive gene clusters encoding transporters and secretion systems, enzymes/toxins, secondary metabolite, biofilm, adhesion and signal response related factors. Further phenotypic analysis of four of these regions shows that the encoded factors cause striking cellular phenotypes relevant to infection biology, including apoptosis, formation of actin 'tails' and multi-nucleation within treated macrophages. The detailed analysis of the remaining host of loci will facilitate genetic dissection of the interaction of this important pathogen with host macrophages and thus further elucidate this critical part of its infection cycle.