Analysis of Sequence Elements Important for Expression and Regulation of the Adenylate Cyclase Gene (Cya) of Salmonella Typhimurium
AUTOR(ES)
Thorner, L. K.
RESUMO
We determined the nucleotide sequence of the regulatory region of the cya gene of Salmonella typhimurium. A set of nested BAL-31 deletions originating upstream of the promoter/regulatory region and extending into the cya structural gene was constructed in M13mp::cya phages and was tested for complementation of a chromosomal cya deletion mutation. BAL-31 deletion mutants unable to complement cya localized the major cya promoter. The synthetic tac promoter was inserted upstream of the BAL-31 deletions so that expression of cya was dependent on transcription from tac. Those tac derivative phages unable to complement cya localized the translation initiation region. The cya DNA sequence revealed at least three potential promoters capable of transcribing cya, with a CRP binding site straddling the -10 hexamer of the promoter proximal to the structural gene. The leader RNA sequence initiated at the latter promoter is approximately 140 bases long and includes a region that may form a stable secondary structure (ΔG = -23.8 kcal). There exist two possible in-frame translation start points, one of which is TTG and the other of which is ATG. The sequence of the S. typhimurium regulatory region was compared with that reported for Escherichia coli.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1204097Documentos Relacionados
- Mutations That Affect Transcription and Cyclic Amp-Crp Regulation of the Adenylate Cyclase Gene (Cya) of Salmonella Typhimurium
- Isolation and expression of the Bradyrhizobium japonicum adenylate cyclase gene (cya) in Escherichia coli.
- Negative regulation of adenylate cyclase gene (cya) expression by cyclic AMP-cyclic AMP receptor protein in Escherichia coli: studies with cya-lac protein and operon fusion plasmids.
- Bordetella pertussis adenylate cyclase toxin and hemolytic activities require a second gene, cyaC, for activation.
- CyaC-mediated activation is important not only for toxic but also for protective activities of Bordetella pertussis adenylate cyclase-hemolysin.