Characterization of the Rickettsia prowazekii pepA gene encoding leucine aminopeptidase.
AUTOR(ES)
Wood, D O
RESUMO
The pepA gene, encoding a protein with leucine aminopeptidase activity, was isolated from Rickettsia prowazekii, an obligate intracellular parasitic bacterium. Nucleotide sequence analysis revealed an open reading frame of 1,502 bp that would encode a protein of 499 amino acids with a calculated molecular weight of 53,892, a size comparable to that of the protein produced in Escherichia coli minicells containing the rickettsial gene. Also, heat-stable leucine aminopeptidase activity was demonstrable in an E. coli peptidase-deficient strain containing R. prowazekii pepA. Comparison of the amino acid sequence of the R. prowazekii PepA with the characterized leucine aminopeptidases from E. coli, Arabidopsis thaliana, and bovine eye lens revealed that 39.8, 34.9, and 34.0% of the residues were identical, respectively. Residues proposed to be part of the active site or involved in the binding of metal ions in the bovine metalloenzyme were all conserved in R. prowazekii PepA. However, despite the structural and enzymatic similarity to E. coli PepA, the R. prowazekii protein was unable to complement the cer site-specific, PepA-dependent recombination system found in E. coli that resolves ColE1-type plasmid multimers into their monomeric forms.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=196109Documentos Relacionados
- xerB, an Escherichia coli gene required for plasmid ColE1 site-specific recombination, is identical to pepA, encoding aminopeptidase A, a protein with substantial similarity to bovine lens leucine aminopeptidase.
- Isolation and characterization of the Rickettsia prowazekii recA gene.
- Characterization of the gene encoding the protective paracrystalline-surface-layer protein of Rickettsia prowazekii: presence of a truncated identical homolog in Rickettsia typhi.
- pepA, a Gene Mediating pH Regulation of Virulence Genes in Vibrio cholerae
- The proteolytic system of Lactobacillus sanfrancisco CB1: purification and characterization of a proteinase, a dipeptidase, and an aminopeptidase.