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Intrinsically disordered protein threads through the bacterial outer-membrane porin OmpF.

ABSTRACT: Porins are ?-barrel outer-membrane proteins through which small solutes and metabolites diffuse that are also exploited during cell death. We have studied how the bacteriocin colicin E9 (ColE9) assembles a cytotoxic translocon at the surface of Escherichia coli that incorporates the trimeric porin OmpF. Formation of the translocon involved ColE9's unstructured N-terminal domain threading in opposite directions through two OmpF subunits, capturing its target TolB on the other side of the membrane in a fixed orientation that triggers colicin import. Thus, an intrinsically disordered protein can tunnel through the narrow pores of an oligomeric porin to deliver an epitope signal to the cell to initiate cell death.

SUBMITTER: Housden NG

PROVIDER: S-EPMC3856478 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Intrinsically disordered protein threads through the bacterial outer-membrane porin OmpF.

Housden Nicholas G NG Hopper Jonathan T S JT Lukoyanova Natalya N Rodriguez-Larrea David D Wojdyla Justyna A JA Klein Alexander A Kaminska Renata R Bayley Hagan H Saibil Helen R HR Robinson Carol V CV Kleanthous Colin C

Science (New York, N.Y.) 20130601 6140

Porins are β-barrel outer-membrane proteins through which small solutes and metabolites diffuse that are also exploited during cell death. We have studied how the bacteriocin colicin E9 (ColE9) assembles a cytotoxic translocon at the surface of Escherichia coli that incorporates the trimeric porin OmpF. Formation of the translocon involved ColE9's unstructured N-terminal domain threading in opposite directions through two OmpF subunits, capturing its target TolB on the other side of the membrane ...[more]

PMID: 23812713

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