Affiliation:
1. Department of Microbiology and Immunology, Stanford University, California 94305.
Abstract
The sequence of the structural gene encoding the Legionella pneumophila extracellular zinc metalloprotease has been determined and was found to possess a single large open reading frame (ORF) of 1,629 nucleotides (nt). This ORF was preceded by consensus promoter (TTAACT . . . 17 nt . . . TATAAC) and ribosome-binding (TAAGGAG) sequences. The deduced polypeptide contained a putative signal sequence and a total of 543 amino acid residues with a computed molecular size of 60,775 daltons, substantially larger than the observed 38,000 daltons of the native and recombinant proteins. A homology search revealed extensive amino acid identity with Pseudomonas aeruginosa elastase, a protein that is also encoded by an ORF substantially larger than that predicted for the mature size of the protein. The structural identity between the L. pneumophila protease and P. aeruginosa elastase was most pronounced in the regions forming the enzymatic active site of elastase. Amino acid residues constituting the active-site cleft of elastase were greater than 75% conserved. Elastase residues that interact with and mediate proteolysis of substrate peptides were 100% conserved. Competitive inhibitors of elastase and the structurally and functionally related thermolysin (phosphoramidon and a phosphoramidate analog, Z-GlyP(O)Leu-Ala), were shown to be equally potent at inhibiting the proteolytic activity of the L. pneumophila protease. These inhibitor studies along with the amino acid sequence similarities provide strong evidence that the L. pneumophila protease and P. aeruginosa elastase share a similar molecular mechanism of proteolysis.
Publisher
American Society for Microbiology
Subject
Molecular Biology,Microbiology
Reference34 articles.
1. Possible role for water dissociation in the slow binding of phosphorus-containing transition-state-analogue inhibitors 'of thermolysin;Bartlett P. A.;Biochemistry,1987
2. Pulmonary damage caused by a protease from Legionella pneumophila;Baskerville A.;Br. J. Exp. Pathol.,1986
3. Cytolytic activity of Legionella pneumophila;Belyi I. F.;Zh. Mikrobiol. Epidemiol. Immunobiol.,1989
4. Molecular characterization and nucleotide sequence of the Pseudomonas aeruginosa elastase structural gene.'J;Bever R. A.;Bacteriol.,1988
5. A rapid alkaline extraction procedure for screening recombinant plasmid DNA;Birnboim H. C.;Nucleic Acids Res.,1979
Cited by
73 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献