Cellular and structural studies of type-IX dependent secretion in Porphyromonas gingivalis.

Abstract

Many bacteria form outer-membrane vesicles (OMVs) via blebbing of their outer-membrane (OM). These function in biofilm-formation, host-invasion, nutrient-acquisition and subversion of host responses. They can diffuse long distances and fuse with other bacteria and hosts, releasing their contents. Porphyromonas gingivalis is a Gram-negative bacterium of the oral cavity that causes chronic periodontitis. It utilizes a type-IX secretion system (T9SS/PorSS) to export virulence factors across its OM. These are covalently attached to the cell surface but also enriched in OMVs. Using molecular microbiology and structural biology techniques this project aims to understanding the links between type IX-dependent secretion and OMV biogenesis.




References:
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Gorasia, D.G., Veith, P.D., Chen, D., Seers, C.A., Mitchell, H.A., Chen, Y-Y., Glew, M.D., Dashper, S.G. & Reynolds, E.c. (2015) Porphyromonas gingivalis Type IX Secretion Substrates Are Cleaved and Modified by a Sortase-Like Mechanism. PLoS Path. 11, e1005152.

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Biological Areas:

Structural Biology
Microbiology

BBSRC Area:

Plants, microbes, food and sustainability