Modulation of the catalytic activity of neutrophil collagenase MMP-8 on bovine collagen I. Role of the activation cleavage and of the hemopexin-like domain.
The cleavage of bovine collagen I by neutrophil collagenase MMP-8 has been followed at pH 7.4, 37 degrees C. The behavior of the whole enzyme molecule (whMMP-8), displaying both the catalytic domain and the hemopexin-like domain, has been compared under the same experimental conditions with that of the catalytic domain only. The main observation is that whMMP-8 cleaves bovine collagen I only at a single specific site, as already reported by many others (Mallya, S. K., Mookhtiar, K. A., Gao, Y., Brew, K., Dioszegi, M., Birkedal-Hansen, H., and van Wart, H. E. (1990) Biochemistry 29, 10628-10634; Knäuper, V., Osthues, A., DeClerk, Y. A., Langley, K. A., Bläser, J., and Tschesche, H. (1993) Biochem. J. 291, 847-854; Marini, S., Fasciglione, G. F., De Sanctis, G., D'Alessio, S., Politi, V., and Coletta, M. (2000) J. Biol. Chem. 275, 18657-18663), whereas the catalytic domain lacks this specificity and cleaves the collagen molecule at multiple sites. Furthermore, a meaningful difference is observed for the cleavage features displayed by two forms of the catalytic domain, which differ for the N terminus resulting from the activation process (i.e. the former Met(80) of the proenzyme (MetMMP-8) and the former Phe(79) of the proenzyme (PheMMP-8)). Thus, the PheMMP-8 species is characterized by a much faster k(cat)/K(m), fully attributable to a lower K(m), suggesting that the conformation of the catalytic domain, induced by the insertion of this N-terminal residue in a specific pocket (Reinemer, P., Grams, F., Huber, R., Kleine, T., Schnierer, S., Piper, M., Tschesche, H., and Bode, W. (1994) FEBS Lett. 338, 227-233), brings about a better, although less discriminatory, recognition process of cleavage site(s) on bovine collagen I.
Gioia
Magda
M
Department of Experimental Medicine and Biochemical Sciences, University of Roma Tor Vergata, Via di Tor Vergata 135, I-00133 Roma, Italy.
Fasciglione
Giovanni Francesco
GF
Marini
Stefano
S
D'Alessio
Silvana
S
De Sanctis
Giampiero
G
Diekmann
Oliver
O
Pieper
Michael
M
Politi
Vincenzo
V
Tschesche
Harald
H
Coletta
Massimo
M
D000818:Animals; D020134:Catalytic Domain; D002417:Cattle; D024042:Collagen Type I / Q000378:metabolism*; D004789:Enzyme Activation; D020784:Matrix Metalloproteinase 8 / Q000737:chemistry / Q000378:metabolism*; D009504:Neutrophils / Q000201:enzymology*
D024042:Collagen Type I; D020784:Matrix Metalloproteinase 8