title: A novel extracellular protease of Vibrio mimicus that mediates maturation of an endogenous hemolysin.
abstract: Vibrio mimicus, a human pathogen that causes gastroenteritis, produces an enterotoxic hemolysin as a virulence factor. The hemolysin is secreted extracellularly as an inactive protoxin and converted to a mature toxin through removal of the N-terminal propeptide, which comprises 151 amino acid residues. In this study, a novel protease having the trypsin-like substrate specificity was purified from the bacterial culture supernatant. The N-terminal amino acid sequence of the purified protein was identical with putative trypsin VMD27150 of V. mimicus strain VM573. The purified protease was found to cause maturation of the protoxin by cleavage of the Arg(151)-Ser(152) bond. Deletion of the protease gene resulted in increased amounts of the protoxin in the culture supernatant. In addition, expression of the hemolysin and protease genes was detected during the logarithmic growth phase. These findings indicate that the protease purified may mediate maturation of the hemolysin.
authors.affiliation: Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1, Tsushima-Naka, Kita-Ku, Okayama, 700-8530, Japan; Collaborative Research Center of Okayama University for Infectious Diseases in India, National Institute of Cholera and Enteric Diseases, 57 Dr. S. C. Banerjee Road, ID Hospital Campus, Beliaghata, Kolkata, West Bengal, 700010, India.
authors.forename: Tamaki
authors.initials: T
authors.lastname: Mizuno
authors.forename: Ayako
authors.initials: A
authors.lastname: Nanko
authors.forename: Yoko
authors.initials: Y
authors.lastname: Maehara
authors.forename: Sumio
authors.initials: S
authors.lastname: Shinoda
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Miyoshi
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D017353:Gene Deletion; D006460:Hemolysin Proteins / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D059748:Proteolysis; D020539:Sequence Analysis, Protein; D044164:Vibrio mimicus / Q000201:enzymology*; D037521:Virulence Factors / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D006460:Hemolysin Proteins; D037521:Virulence Factors; C073845:hemolysin, Vibrio; D010447:Peptide Hydrolases
keywords: Vibrio mimicus; hemolysin; maturation; protease