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The membrane localization domains of two distinct bacterial toxins form a 4-helix-bundle in solution.

ABSTRACT: Membrane localization domain (MLD) was first proposed for a 4-helix-bundle motif in the crystal structure of the C1 domain of Pasteurella multocida toxin (PMT). This structure motif is also found in the crystal structures of several clostridial glycosylating toxins (TcdA, TcdB, TcsL, and TcnA). The Ras/Rap1-specific endopeptidase (RRSP) module of the multifunctional autoprocessing repeats-in-toxins (MARTX) toxin produced by Vibrio vulnificus has sequence homology to the C1-C2 domains of PMT, including a putative MLD. We have determined the solution structure for the MLDs in PMT and in RRSP using solution state NMR. We conclude that the MLDs in these two toxins assume a 4-helix-bundle structure in solution.

SUBMITTER: Hisao GS

PROVIDER: S-EPMC5326565 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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The membrane localization domains of two distinct bacterial toxins form a 4-helix-bundle in solution.

Hisao Grant S GS Brothers Michael C MC Ho Mengfei M Wilson Brenda A BA Rienstra Chad M CM

Protein science : a publication of the Protein Society 20170214 3

Membrane localization domain (MLD) was first proposed for a 4-helix-bundle motif in the crystal structure of the C1 domain of Pasteurella multocida toxin (PMT). This structure motif is also found in the crystal structures of several clostridial glycosylating toxins (TcdA, TcdB, TcsL, and TcnA). The Ras/Rap1-specific endopeptidase (RRSP) module of the multifunctional autoprocessing repeats-in-toxins (MARTX) toxin produced by Vibrio vulnificus has sequence homology to the C1-C2 domains of PMT, inc ...[more]

PMID: 27977897

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