Type III Secretion in the Melioidosis Pathogen Burkholderia pseudomallei

• Published in: Frontiers in cellular and infection microbiology Vol. 7; p. 255
• Main Authors: Vander Broek, Charles W, Stevens, Joanne M
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 15.06.2017
• Subjects: Animals; Bacterial Proteins - genetics; Bacterial Proteins - immunology; Bacterial Proteins - metabolism; Burkholderia pseudomallei; Burkholderia pseudomallei - immunology; Burkholderia pseudomallei - metabolism; Burkholderia pseudomallei - pathogenicity; Cricetinae; effector; Gene Expression Regulation, Bacterial; Humans; melioidosis; Melioidosis - metabolism; Melioidosis - microbiology; Mice; Microbiology; Molecular Chaperones - metabolism; Mutation; Plant Diseases - microbiology; Salmonella - metabolism; Shigella flexneri - metabolism; T3SS; translocator; Type III Secretion Systems - chemistry; Type III Secretion Systems - classification; Type III Secretion Systems - genetics; Type III Secretion Systems - metabolism; Virulence Factors - metabolism; T3SS; Burkholderia pseudomallei; effector; melioidosis; translocator
• ISSN: 2235-2988; 2235-2988
• DOI: 10.3389/fcimb.2017.00255

is a Gram-negative intracellular pathogen and the causative agent of melioidosis, a severe disease of both humans and animals. Melioidosis is an emerging disease which is predicted to be vastly under-reported. Type III Secretion Systems (T3SSs) are critical virulence factors in Gram negative pathogens of plants and animals. The genome of encodes three T3SSs. T3SS-1 and -2, of which little is known, are homologous to Hrp2 secretion systems of the plant pathogens and . T3SS-3 is better characterized and is homologous to the Inv/Mxi-Spa secretion systems of spp. and , respectively. Upon entry into the host cell, requires T3SS-3 for efficient escape from the endosome. T3SS-3 is also required for full virulence in both hamster and murine models of infection. The regulatory cascade which controls T3SS-3 expression and the secretome of T3SS-3 have been described, as well as the effect of mutations of some of the structural proteins. Yet only a few effector proteins have been functionally characterized to date and very little work has been carried out to understand the hierarchy of assembly, secretion and temporal regulation of T3SS-3. This review aims to frame current knowledge of T3SSs in the context of other well characterized model T3SSs, particularly those of and .