EXPRESSION OF HUMAN PRO-MATRIX METALLOPROTEINASE-3 THAT LACKS THE N-TERMINAL-34 RESIDUES IN ESCHERICHIA-COLI - AUTOACTIVATION AND INTERACTION WITH TISSUE INHIBITOR OF METALLOPROTEINASE-1 (TIMP-1)
K. Suzuki et al., EXPRESSION OF HUMAN PRO-MATRIX METALLOPROTEINASE-3 THAT LACKS THE N-TERMINAL-34 RESIDUES IN ESCHERICHIA-COLI - AUTOACTIVATION AND INTERACTION WITH TISSUE INHIBITOR OF METALLOPROTEINASE-1 (TIMP-1), Biological chemistry, 379(2), 1998, pp. 185-191
Human pro-matrix metalloproteinase 3 (proMMP-3) tacking the N-terminal
34 amino acids and the C-terminal hemopexin-like domain was expressed
in E. coli and used to investigate the process of proenzyme activatio
n and its interaction with an endogenous inhibitor TIMP-1 during activ
ation. The truncated precursor was purified from the E. coli extract i
n the presence of 5mM EGTA. The active 23.5 kDa form was generated sim
ply by exposure to Ca2+ and Zn2+ but not either by Ca2+ alone or by Zn
2+ alone. The rate of MMP-3(Delta C) formation was concentration depen
dent, indicating that autoactivation is a bimolecular reaction. The tr
uncated precursor was able to interact with the N-terminal domain of T
IMP-1 without losing the 48 residue-long propeptide. However, upon a l
onger incubation, the propeptide was slowly processed, indicating that
the association of the N-terminally truncated proMMP-3 with TIMP-1 is
weaker than that of the fully activated MMP-3 and TIMP-1. These resul
ts indicate that the expression of MMP activities is regulated by endo
genous inhibitor TIMPs during their activation processes which provide
an additional control mechanism of extracellular matrix breakdown.