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Molecular ruler determines needle length for the Salmonella Spi-1 injectisome.

ABSTRACT: The type-III secretion (T3S) systems of bacteria are part of self-assembling nanomachines: the bacterial flagellum that enables cells to propel themselves through liquid and across hydrated surfaces, and the injectisome that delivers pathogenic effector proteins into eukaryotic host cells. Although the flagellum and injectisome serve different purposes, they are evolutionarily related and share many structural similarities. Core features to these T3S systems are intrinsic length control mechanisms for external cellular projections: the hook of the flagellum and the injectisome needle. We present evidence that the Spi-1 injectisome, like the Salmonella flagellar hook, uses a secreted molecular ruler, InvJ, to determine needle length. This result supports a universal length control mechanism using molecular rulers for T3S systems.

SUBMITTER: Wee DH

PROVIDER: S-EPMC4386390 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Molecular ruler determines needle length for the Salmonella Spi-1 injectisome.

Wee Daniel H DH Hughes Kelly T KT

Proceedings of the National Academy of Sciences of the United States of America 20150316 13

The type-III secretion (T3S) systems of bacteria are part of self-assembling nanomachines: the bacterial flagellum that enables cells to propel themselves through liquid and across hydrated surfaces, and the injectisome that delivers pathogenic effector proteins into eukaryotic host cells. Although the flagellum and injectisome serve different purposes, they are evolutionarily related and share many structural similarities. Core features to these T3S systems are intrinsic length control mechanis ...[more]

PMID: 25775540

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