Pertussis toxin and target eukaryotic cells: binding, entry, and activation.
Pertussis toxin, a protein virulence factor produced by Bordetella pertussis, is composed of an A protomer and a B oligomer. The A protomer consists of a single polypeptide, termed the S1 subunit, which disrupts transmembrane signaling by ADP-ribosylating eukaryotic G-proteins. The B oligomer, containing five polypeptides, binds to cell receptors (most likely containing carbohydrate) and delivers the S1 subunit. Current knowledge suggests that expression of ADP-ribosyltransferase activity in target eukaryotic cells arises after 1) nucleotides and membrane lipids allosterically promote the release of the S1 subunit; and 2) the single disulfide bond in the S1 subunit is reduced by reductants such as glutathione. This model suggests conditions for the proper use of the toxin as an experimental reagent.
Kaslow
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Department of Physiology, University of Southern California, School of Medicine, Los Angeles 90033.
Burns
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D000818:Animals; D001692:Biological Transport; D002240:Carbohydrate Sequence; D006224:Cricetinae; D005057:Eukaryotic Cells / Q000187:drug effects / Q000378:metabolism; D008969:Molecular Sequence Data; D037342:Pertussis Toxin; D010566:Virulence Factors, Bordetella / Q000378:metabolism* / Q000494:pharmacology
D010566:Virulence Factors, Bordetella; D037342:Pertussis Toxin