Dataset Information

Quantitative proteomic analysis of Burkholderia pseudomallei Bsa Type III secretion system effectors using hyper-secreting mutants

ABSTRACT: Burkholderia pseudomallei is an intracellular pathogen and the causative agent of melioidosis, a severe disease of humans and animals. One of the virulence factors critical for early stages of infection is the Burkholderia secretion apparatus (Bsa) Type 3 Secretion System (T3SS), a molecular syringe that injects bacterial proteins, called effectors, into eukaryotic cells where they subvert cellular functions to the benefit of the bacteria. While the Bsa T3SS itself is known to be important for invasion, intracellular replication, and virulence, only a few genuine effector proteins have been identified and the complete repertoire of proteins secreted by the system has not yet been fully characterised. We constructed a mutant lacking bsaP, a homologue of the T3SS gatekeeper family of proteins that exert control over the timing and magnitude of effector protein secretion. Mutants lacking BsaP, or the T3SS translocon protein BipD, were observed to hyper-secrete the known Bsa effector protein BopE, providing evidence of their role in post-translational control of the Bsa T3SS and representing key reagents for the identification of its secreted substrates. Isobaric Tags for Relative and Absolute Quantification (iTRAQ), a gel-free quantitative proteomics technique, was used to compare the secreted protein profiles of the Bsa T3SS hyper-secreting mutants of B. pseudomallei with the isogenic parent strain and a bsaZ mutant incapable of effector protein secretion. Our study provides one of the most comprehensive core secretomes of B. pseudomallei described to date and identified 26 putative Bsa-dependent secreted proteins that may be considered candidate effectors. Two of these proteins, BprD and BapA, were validated as novel effector proteins secreted by the Bsa T3SS of B. pseudomallei.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Burkholderia Pseudomallei (strain K96243)

TISSUE(S): Culture Supernatant, Prokaryotic Cell

DISEASE(S): Melioidosis

SUBMITTER: Charles Vander Broek

LAB HEAD: Jo M. Stevens

PROVIDER: PXD001656 | Pride | 2015-01-28

REPOSITORIES: Pride

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Quantitative proteomic analysis of Burkholderia pseudomallei Bsa type III secretion system effectors using hypersecreting mutants.

Vander Broek Charles W CW Chalmers Kevin J KJ Stevens Mark P MP Stevens Joanne M JM

Molecular & cellular proteomics : MCP 20150129 4

Burkholderia pseudomallei is an intracellular pathogen and the causative agent of melioidosis, a severe disease of humans and animals. One of the virulence factors critical for early stages of infection is the Burkholderia secretion apparatus (Bsa) Type 3 Secretion System (T3SS), a molecular syringe that injects bacterial proteins, called effectors, into eukaryotic cells where they subvert cellular functions to the benefit of the bacteria. Although the Bsa T3SS itself is known to be important fo ...[more]

PMID: 25635268

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Dataset Information

Quantitative proteomic analysis of Burkholderia pseudomallei Bsa Type III secretion system effectors using hyper-secreting mutants

Publications

Quantitative proteomic analysis of Burkholderia pseudomallei Bsa type III secretion system effectors using hypersecreting mutants.

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