2TCL:
reference: Structure of the catalytic domain of human fibroblast collagenase complexed with an inhibitor., Borkakoti N, Winkler FK, Williams DH, D'Arcy A, Broadhurst MJ, Brown PA, Johnson WH, Murray EJ, Nat Struct Biol 1994 Feb;1(2):106-10. PMID: 7656013

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