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Post‐translational modification of matrix metalloproteinase‐2 by peroxynitrite
Author(s) -
Nicolescu Adrian C,
Viappiani Serena,
Holt Andrew,
Schulz Richard
Publication year - 2008
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.22.1_supplement.750.20
Subject(s) - peroxynitrite , chemistry , matrix metalloproteinase , biochemistry , glutathione , enzyme , intracellular , biophysics , superoxide , biology
Matrix metalloproteinases (MMPs) are key enzymes in the development and remodeling of tissues. Disruption of the interaction between a conserved Cys residue in the propeptide domain and Zn 2+ in the catalytic site activates MMPs. Enhanced biosynthesis of peroxynitrite (ONOO‾) is implicated in heart failure and myocardial ischemia/reperfusion (I/R) injury, where activated MMP‐2 was shown to degrade important intracellular targets, e.g. troponin I (TnI), myosin light chain‐1 and α‐actinin. We investigated the mechanisms by which ONOO‾ may activate full length 72 kDa MMP‐2 in vitro. Challenging MMP‐2 with ONOO‾ resulted in a biphasic change in MMP‐2 activity, with low μM ONOO‾ increasing and high μM reducing its activity. Changes in the V max of the enzyme and no significant effect on the K M were observed using a synthetic fluorogenic substrate. Addition of glutathione (GSH) did not potentiate the effect of ONOO‾, but prevented the loss of MMP‐2 activity induced by higher concentrations of ONOO‾. Mass spectrometry analysis of the reaction of ONOO‾ with either MMP‐2 or synthetic peptide KPRCGNPDVANYNFFPR identified several structural modifications, including sulfhydryl oxidation and, in the presence of GSH, reversible glutathiolation of the critical Cys. These data suggest that ONOO‾ can modify the critical Cys of the propeptide domain in MMP‐2 and that may be responsible for its activation in the heart.