Gs. Butler et al., The specificity of TIMP-2 for matrix metalloproteinases can be modified bysingle amino acid mutations, J BIOL CHEM, 274(29), 1999, pp. 20391-20396
Residues 1-127 of human TIMP-8 (N-TIMP-2), comprising three of the disulfid
e-bonded loops of the TIMP-8 molecule, is a discrete protein domain that fo
lds independently of the C-terminal domain. This domain has been shown to b
e necessary and sufficient for metalloproteinase inhibition and contains th
e major sites of interaction with the catalytic N-terminal domain of active
matrix metalloproteinases (MMPs), Residues identified as being involved in
the interaction with MMPs by NMR chemical shift perturbation studies and T
IMP/MMP crystal structures have been altered by site directed mutagenesis.
We show, by measurement of association rates and apparent inhibition consta
nts, that the specificity of these N-TIMP-2 mutants for a range of MMPs can
be altered by single site mutations in either the TIMP "ridge" (Cys(1)-Cys
(3) and Ser(68)-Cys(72)) Or the flexible AB loop (Ser(31)-Ile(41)). This wo
rk demonstrates that it is possible to engineer TIMPs with altered specific
ity and suggests that this form of protein engineering may be useful in the
treatment of diseases such as arthritis and cancer where the selective inh
ibition of key MMPs is desirable.