Serine 0- complex, crystal structure

Grtitter, M.G., et al. Crystal structure of the thrombin-hirudin complex a novel mode of serine protease inhibition. EMBO J. 9 2361-2365, 1990. 

The crystal structure of the HNL isolated from S. bicolor (SbHNL) was determined in a complex with the inhibitor benzoic acid." The folding pattern of SbHNL is similar to that of wheat serine carboxypeptidase (CP-WII)" and alcohol dehydrogenase." A unique two-amino acid deletion in SbHNL, however, is forcing the putative active site residues away from the hydrolase binding site toward a small hydrophobic cleft, thereby defining a completely different active site architecture where the triad of a carboxypeptidase is missing. 

The initial solution of the crystal structure of the Torpedo enzyme [28], followed by the mammalian AChE structure [29], revealed that the active center serine lies at the base of a rather narrow gorge that is lined heavily with aromatic residues (Fig. 11-6). The enzyme carries a net negative charge, and an electrostatic dipole is oriented on the enzyme to facilitate diffusional entry of cationic ligands. Crystal structures of several inhibitors in a complex with AChE also have been elucidated [25]. 

Nassar, N., Horn, G., Herrmann, C., Scherer, A., McCormick, F., and WiTTiNGHOFER, A., The 2.2 A crystal structure of the Ras-binding domain of the serine/threonine kinase c-RafL in complex with RaplA and a GTP analogue. Nature, 1995, 375, 554. 

The three-dimensional structure of the tryptophan synthase 02)82 complex from S. typhimurium reveals that the four polypeptide subunits are arranged in an extended a/8/Jo order forming a complex 150 A long.7 A schematic view of a single a/ ft pair based on the crystal structure is shown in the color plate . The 02)82 complex catalyzes the synthesis of L-tryptophan from indole-3-glycerol phosphate and L-serine, termed the a)3 reaction (Fig. 7.1). The a and )3 subunits can be separated and shown to catalyze two distinct reactions, termed the a and / reactions, respectively (Fig. 7.1). The rates of the a and / reactions are greatly increased when catalyzed by the 02)82 complex. Although the o)3 reaction is formally the sum of the a and )3 reactions, indole does not appear as a free intermediate in solution in this reaction.17-21 This result indicates that indole is a... 

Xu Y, Carr PD, Guss JM, Ollis DL. The crystal structure of bikunin from the inter-a-inhibitor complex A serine protease inhibitor with two kunitz domains. J Mol Biol 1998 276 955-966. 

Mayer, M. L., Olson, R., and Gouaux, E. (2001). Mechanisms for ligand binding to GluRO ion channels Crystal structures of the glutamate and serine complexes and a closed apo state./. Mol. Biol. 311, 815-836. 

J. Koepke, U. Ermler, E. Warkentin, G. Wenzl, and P. Flecker. 2000. Crystal structure of cancer chemopreventive Bowman-Birk inhibitor in ternary complex with bovine trypsin at 2.3 A resolution Structural basis of Janus-faced serine protease inhibitor specificity J. Mol. Biol. 298 477-491. (PubMed)... 

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