1c8t
From Proteopedia
HUMAN STROMELYSIN-1 (E202Q) CATALYTIC DOMAIN COMPLEXED WITH RO-26-2812
Overview
Human stromelysin-1 is a member of the matrix metalloproteinase (MMP) family of enzymes. The active site glutamic acid of the MMPs is conserved throughout the family and plays a pivotal role in the catalytic mechanism. The structural and functional consequences of a glutamate to glutamine substitution in the active site of stromelysin-1 were investigated in this study. In contrast to the wild-type enzyme, the glutamine-substituted mutant was not active in a zymogram assay where gelatin was the substrate, was not activated by organomercurials and showed no activity against a peptide substrate. The glutamine-substituted mutant did, however, bind to TIMP-1, the tissue inhibitor of metalloproteinases, after cleavage of the propeptide with trypsin. A second construct containing the glutamine substitution but lacking the propeptide was also inactive in the proteolysis assays and capable of TIMP-1 binding. X-ray structures of the wild-type and mutant proteins complexed with the propeptide-based inhibitor Ro-26-2812 were solved and in both structures the inhibitor binds in an orientation the reverse of that of the propeptide in the pro-form of the enzyme. The inhibitor makes no specific interactions with the active site glutamate and a comparison of the wild-type and mutant structures revealed no major structural changes resulting from the glutamate to glutamine substitution.
About this Structure
1C8T is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Expression, characterization and structure determination of an active site mutant (Glu202-Gln) of mini-stromelysin-1., Steele DL, El-Kabbani O, Dunten P, Windsor LJ, Kammlott RU, Crowther RL, Michoud C, Engler JA, Birktoft JJ, Protein Eng. 2000 Jun;13(6):397-405. PMID:10877850 Page seeded by OCA on Fri May 2 12:28:15 2008
