Figure 6.

Structure analysis and identification of potentially important amino acid residues for the α3β1-binding activity of TIMP-2 localized to the B-C loop. a) Structure of TIMP-2 viewed perpendicular to the long axis of the N-terminal OB fold. Blue denotes β-sheets, red denotes α-helices and yellow denotes loop structures. N is the amino terminal cysteine and C is the carboxyl terminal alanine residue. Also shown is the surface localization of the charged residues of the 23 amino acid α3β1-binding region of the B-C loop. b) Structure of TIMP-2 viewed from below, all other designations are the same as in A. c) B-C loops of TIMP-2 and TIMP-1 overlaid and viewed perpendicular to the long axis of the OB fold, demonstrating the kink induced by Pro⁵⁶ that results in projection of the charged amino acid residues Glu⁵⁷, Lys⁵⁸, Asp⁵⁹ and Glu⁶¹ of the 24 amino acid α3β1-binding domain away from the interior of the OB fold towards the surface of the TIMP-2 molecule. d) B-C loops of TIMP-2 and TIMP-1 viewed from above again showing projection of amino acid residues Glu⁵⁷, Lys⁵⁸, Asp⁵⁹ and Glu⁶¹ towards the surface and away from the interior of the TIMP-2 molecule.