title: Physicochemical and biological properties of an extracellular serine protease of Aeromonas sobria.
abstract: Previously, we cloned a protease gene of Aeromonas sobria, determined its nucleotide sequence and established a method of purifying its product. In this study, we examined the properties of the purified protease. The protease was temperature-labile and had an optimal pH of 7.5. Metallo-protease inhibitors and a cysteine protease inhibitor did not block the proteolytic activity of the enzyme. The treatment with reagents to modify sulfhydryl group did not reduce the activity. But, serine protease inhibitors did, showing that it was a serine protease. Subsequently, we examined the ability of the protease to enhance vascular permeability in dorsal skin. The protease showed activity and the reaction was inhibited by a simultaneously injected antihistaminic agent. Histopathological examination showed that mast cells appeared around the site where the protease was injected. These findings show that the vascular permeability-enhancing effect of the protease is due to histamine released at the site. Furthermore, we found that a soybean trypsin inhibitor (Kunitz) did not block the proteolytic action of the protease in vitro, but inhibited its vascular permeability-enhancing activity in skin. This suggests that a trypsin-like protease from skin mediates the activity of the protease to enhance its vascular permeability.
authors.affiliation: Institute of Pharmacognosy, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima, Japan.
authors.forename: Ritsuko
authors.initials: R
authors.lastname: Yokoyama
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Fujii
authors.forename: Yoko
authors.initials: Y
authors.lastname: Noguchi
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Nomura
authors.forename: Masahiko
authors.initials: M
authors.lastname: Akita
authors.forename: Kojun
authors.initials: K
authors.lastname: Setsu
authors.forename: Shigeo
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Keinosuke
authors.initials: K
authors.lastname: Okamoto
mesh_terms: D000333:Aeromonas / Q000201:enzymology*; D000818:Animals; D002199:Capillary Permeability / Q000187:drug effects / Q000502:physiology; D002364:Caseins / Q000378:metabolism; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D006651:Histocytochemistry; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D051381:Rats; D017208:Rats, Wistar; D012697:Serine Endopeptidases / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D015842:Serine Proteinase Inhibitors / Q000494:pharmacology; D012867:Skin / Q000098:blood supply; D013439:Sulfhydryl Reagents / Q000494:pharmacology
chemical_list: D002364:Caseins; D006634:Histamine H1 Antagonists; D015842:Serine Proteinase Inhibitors; D013439:Sulfhydryl Reagents; D012697:Serine Endopeptidases