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A host-specific factor is necessary for efficient folding of the autotransporter plasmid-encoded toxin.

ABSTRACT: Autotransporters are the most common virulence factors secreted from Gram-negative pathogens. Until recently, autotransporter folding and outer membrane translocation were thought to be self-mediated events that did not require accessory factors. Here, we report that two variants of the autotransporter plasmid-encoded toxin are secreted by a lab strain of Escherichia coli. Biophysical analysis and cell-based toxicity assays demonstrated that only one of the two variants was in a folded, active conformation. The misfolded variant was not produced by a pathogenic strain of enteroaggregative E. coli and did not result from protein overproduction in the lab strain of E. coli. Our data suggest a host-specific factor is required for efficient folding of plasmid-encoded toxin.

SUBMITTER: Nemec KN

PROVIDER: S-EPMC2823069 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature

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A host-specific factor is necessary for efficient folding of the autotransporter plasmid-encoded toxin.

Nemec Kathleen N KN Scaglione Patricia P Navarro-García Fernando F Huerta Jazmín J Tatulian Suren A SA Teter Ken K

Biochimie 20091126 2

Autotransporters are the most common virulence factors secreted from Gram-negative pathogens. Until recently, autotransporter folding and outer membrane translocation were thought to be self-mediated events that did not require accessory factors. Here, we report that two variants of the autotransporter plasmid-encoded toxin are secreted by a lab strain of Escherichia coli. Biophysical analysis and cell-based toxicity assays demonstrated that only one of the two variants was in a folded, active c ...[more]

PMID: 19944129

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X-ray crystal structure of the passenger domain of plasmid encoded toxin(Pet), an autotransporter enterotoxin from enteroaggregative Escherichia coli (EAEC).

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2023-08-10 | MTBLS7248 | MetaboLights

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Intracellular expression of the plasmid-encoded toxin from enteroaggregative Escherichia coli.

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Structural characteristics of the plasmid-encoded toxin from enteroaggregative Escherichia coli.

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Giant plasmid-encoded polyketide synthases produce the macrolide toxin of Mycobacterium ulcerans.

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