Isolation and characterization of Ca2+-blind mutants of Yersinia pestis.
AUTOR(ES)
Yother, J
RESUMO
The plasmid pCD1 is required for expression of the low-calcium response (LCR), virulence, and production of V antigen in Yersinia pestis KIM. Five independent mutants constitutive for the LCR at 37 degrees C (Lcrc) were obtained through ethyl methanesulfonate mutagenesis followed by ampicillin enrichment. A sixth, spontaneous mutant was obtained directly through ampicillin enrichment. These mutants failed to grow at 37 degrees C regardless of calcium concentration and produced V antigen constitutively at this temperature. All six mutations were located on pCD1. One mutation was mapped to a 1-kilobase region of lcrA. Based on complementation mapping of this mutation, the lcrA locus was divided into two new loci, lcrD and lcrE. This mutation, lcrE1, did not alter the transcription of other genes in the LCR region and was cis-recessive to lcr mutations. Several lower-molecular-weight outer membrane proteins which were observed in the parent strain grown at 37 degrees C in the presence of 2.5 mM calcium were reduced in quantity or absent from the mutant strain.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=214309Documentos Relacionados
- Transport of Ca2+ by Yersinia pestis.
- A low-Ca2+ response operon encodes the V antigen of Yersinia pestis.
- Consequences of Ca2+ deficiency on macromolecular synthesis and adenylate energy charge in Yersinia pestis.
- Effect of exogenous nucleotides on Ca2+ dependence and V antigen synthesis in Yersinia pestis.
- lcrR, a low-Ca2(+)-response locus with dual Ca2(+)-dependent functions in Yersinia pestis.