title: Comparison of the Vibrio cholerae hemagglutinin/protease and the Pseudomonas aeruginosa elastase.
abstract: The soluble hemagglutinin/protease (HA/protease) produced by Vibrio cholerae and the elastase of Pseudomonas aeruginosa are both zinc/calcium-dependent proteases. In the present study the two enzymes are compared immunologically and functionally. The N-terminal amino acid sequences of the proteins had 65% identity within the first 20 amino acids. Polyclonal antisera against each purified protein recognized the enzyme of the other species in enzyme-linked immunosorbent assay, checkerboard immunoblot, and Western blot analyses and inhibited the protease activity of both enzymes in milk and elastin agars. Like the HA/protease, the elastase hemagglutinated "responder" but not "nonresponder" chicken erythrocytes, degraded ovomucin, lactoferrin, and fibronectin, and nicked the A subunit of the cholera toxin-related heat-labile enterotoxin from Escherichia coli. Whereas none of the three proteases tested (elastase, HA/protease, or pronase E) had any obvious effect in ileal loop tests in rabbits at doses up to 50 micrograms, all three produced some detectable skin reactions at a dose of 0.1 micrograms and necrosis at a higher dose (i.e., 5 micrograms). We conclude that the V. cholerae HA/protease and the P. aeruginosa elastase are structurally, functionally, and immunologically related.
authors.affiliation: Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri-Columbia 65212.
authors.forename: C C
authors.initials: CC
authors.lastname: Häse
authors.forename: R A
authors.initials: RA
authors.lastname: Finkelstein
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001422:Bacterial Adhesion; D003429:Cross Reactions; D010450:Endopeptidases / Q000032:analysis* / Q000276:immunology / Q000633:toxicity; D006388:Hemagglutinins / Q000032:analysis* / Q000276:immunology / Q000633:toxicity; D008969:Molecular Sequence Data; D010196:Pancreatic Elastase / Q000032:analysis* / Q000276:immunology / Q000633:toxicity; D011550:Pseudomonas aeruginosa / Q000201:enzymology*; D011817:Rabbits; D014734:Vibrio cholerae / Q000201:enzymology* / Q000472:pathogenicity
chemical_list: D006388:Hemagglutinins; D010450:Endopeptidases; D010196:Pancreatic Elastase