title: Modulation of the proteolytic activity of matrix metalloproteinase-2 (gelatinase A) on fibrinogen.
abstract: The proteolytic processing of bovine fibrinogen by MMP-2 (gelatinase A), which brings about the formation of a product unable to form fibrin clots, has been studied at 37 degrees C. Catalytic parameters, although showing a somewhat lower catalytic efficiency with respect to thrombin and plasmin, indeed display values indicating a pathophysiological significance of this process. A parallel molecular modelling study predicts preferential binding of MMP-2 to the beta-chain of fibrinogen through its haemopexin-like domain, which has been directly demonstrated by the inhibitory effect in the presence of the exogenous haemopexin-like domain. However, the removal of this domain does not impair the interaction between MMP-2 and fibrinogen, but it dramatically alters the proteolytic mechanism, producing different fragmentation intermediates. The investigation at various pH values between 6.0 and 9.3 indicates a proton-linked behaviour, which is relevant for interpreting the influence on the process by environmental conditions occurring at the site of an injury. Furthermore, the action of MMP-2 on peroxynitrite-treated fibrinogen has been investigated, a situation possibly occurring under oxidative stress. The chemical alteration of fibrinogen, which has been shown to abolish its clotting activity, brings about only limited modifications of the catalytic parameters without altering the main enzymatic mechanism.
authors.affiliation: Department of Experimental Medicine and Biochemical Sciences, University of Roma Tor Vergata, Via Montpellier 1, I-00133 Roma, Italy.
authors.forename: Susanna
authors.initials: S
authors.lastname: Monaco
authors.forename: Magda
authors.initials: M
authors.lastname: Gioia
authors.forename: Janet
authors.initials: J
authors.lastname: Rodriguez
authors.forename: Giovanni Francesco
authors.initials: GF
authors.lastname: Fasciglione
authors.forename: Donato
authors.initials: D
authors.lastname: Di Pierro
authors.forename: Giulio
authors.initials: G
authors.lastname: Lupidi
authors.forename: Ludwig
authors.initials: L
authors.lastname: Krippahl
authors.forename: Stefano
authors.initials: S
authors.lastname: Marini
authors.forename: Massimo
authors.initials: M
authors.lastname: Coletta
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D002384:Catalysis; D002417:Cattle; D005340:Fibrinogen / Q000737:chemistry / Q000378:metabolism*; D006466:Hemopexin / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D020778:Matrix Metalloproteinase 2 / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D030421:Peroxynitrous Acid; D020836:Protein Structure, Quaternary
chemical_list: D030421:Peroxynitrous Acid; D005340:Fibrinogen; D006466:Hemopexin; D020778:Matrix Metalloproteinase 2