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Timing is everything: the regulation of type III secretion.

ABSTRACT: Type Three Secretion Systems (T3SSs) are essential virulence determinants of many Gram-negative bacteria. The T3SS is an injection device that can transfer bacterial virulence proteins directly into host cells. The apparatus is made up of a basal body that spans both bacterial membranes and an extracellular needle that possesses a channel that is thought to act as a conduit for protein secretion. Contact with a host-cell membrane triggers the insertion of a pore into the target membrane, and effectors are translocated through this pore into the host cell. To assemble a functional T3SS, specific substrates must be targeted to the apparatus in the correct order. Recently, there have been many developments in our structural and functional understanding of the proteins involved in the regulation of secretion. Here we review the current understanding of protein components of the system thought to be involved in switching between different stages of secretion.

SUBMITTER: Deane JE

PROVIDER: S-EPMC2835726 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Timing is everything: the regulation of type III secretion.

Deane Janet E JE Abrusci Patrizia P Johnson Steven S Lea Susan M SM

Cellular and molecular life sciences : CMLS 20091231 7

Type Three Secretion Systems (T3SSs) are essential virulence determinants of many Gram-negative bacteria. The T3SS is an injection device that can transfer bacterial virulence proteins directly into host cells. The apparatus is made up of a basal body that spans both bacterial membranes and an extracellular needle that possesses a channel that is thought to act as a conduit for protein secretion. Contact with a host-cell membrane triggers the insertion of a pore into the target membrane, and eff ...[more]

PMID: 20043184

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