title: The Vwa+ virulence factor of yersiniae: the molecular basis of the attendant nutritional requirement for Ca++.
abstract: The plague V antigen is a cytoplasmic 90,000-dalton peptide, and the W antigen is a primarily extracellular 145,000-dalton lipoprotein of unknown origin. Wild-type yersiniae undergo restriction of cell division when producing these plasmid-mediated virulence antigens (Vwa+) during cultivation at 37 C in Ca++-deficient media. In Yersinia pestis both restriction and synthesis of V and W antigens are potentiated in this environment by elevated Mg++ and prevented by Ca++ or exogenous nucleoside triphosphates. Restriction occurs by mechanisms that also are involved in nutritional stepdown (shutoff of stable RNA synthesis with reduction of nucleotide pools). Attendant regulatory mechanisms remain undefined; they are independent of MS nucleotides but may involve V antigen. Restriction is similar in Vwa+ Yersinia pseudotuberculosis and Yersinia enterocolitica, which, unlike Y. pestis, produce ancillary outer membrane peptides. Synthesis of these activities is dependent on elevated temperature but may not be influenced by Ca++; their presence is associated with spontaneous autoagglutination in vitro.
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000032:analysis* / Q000235:genetics / Q000633:toxicity; D002118:Calcium / Q000172:deficiency / Q000494:pharmacology*; D000939:Epitopes / Q000032:analysis; D006801:Humans; D014774:Virulence; D015007:Yersinia / Q000254:growth & development / Q000472:pathogenicity*
chemical_list: D000942:Antigens, Bacterial; D000939:Epitopes; D002118:Calcium