GEOMETRY OF BINDING OF THE NALPHA-TOSYLATED PIPERIDIDES OF M-AMIDINO-, P-AMIDINO-AND P-GUANIDINO PHENYLALANINE TO THROMBIN AND TRYPSIN: X-RAY CRYSTAL STRUCTURES OF THEIR TRYPSIN COMPLEXES AND MODELING OF THEIR THROMBIN COMPLEXES
Geometry of binding of the N alpha-tosylated piperidides of m-amidino-, p-amidino- and p-guanidino phenylalanine to thrombin and trypsin. X-ray crystal structures of their trypsin complexes and modeling of their thrombin complexes.
Primary Citation of Related Structures:   1PPH
PubMed Abstract: 
The X-ray crystal structures of the complexes formed with bovine trypsin and the N alpha-tosylated piperidides of m-amidino-, p-amidino- and p-guanidino-D,L-phenylalanine (3-TAPAP, 4-TAPAP and 4-TGPAP) were determined with data to 1.8 A resolution. The L-stereoisomer of 3-TAPAP binds as a compact entity into the active site of trypsin, with the amidino and the carbonyl groups of the central amidinophenylalanyl residue hydrogen-bonded to Gly216 of trypsin ...
The X-ray crystal structures of the complexes formed with bovine trypsin and the N alpha-tosylated piperidides of m-amidino-, p-amidino- and p-guanidino-D,L-phenylalanine (3-TAPAP, 4-TAPAP and 4-TGPAP) were determined with data to 1.8 A resolution. The L-stereoisomer of 3-TAPAP binds as a compact entity into the active site of trypsin, with the amidino and the carbonyl groups of the central amidinophenylalanyl residue hydrogen-bonded to Gly216 of trypsin. According to modeling and energy minimization, 3-TAPAP fits perfectly in this conformation to the more restrictive thrombin active site also (Bajusz et al. (1978) Int. J. Pept. Prot. Res. 12, 217-221); the piperidine moiety extends into the cage-like S2 subsite of thrombin, but leaves room for additional substituents which might help to improve binding and pharmacological properties. In contrast, 4-TAPAP and 4-TGPAP bind only weakly and in an extended conformation to trypsin; their considerably enhanced affinities for thrombin would suggest a more compact binding to thrombin.
Related Citations: 
Geometry of Binding of the Benzamidine-and Arginine-Based Inhibitors N Alpha-(2-Naphthyl-Sulphonyl-Glycyl)-Dl-P-Amidinophenylalanyl-Piperidine (Napap) and (2R,4R)-4-Methyl-1-[N Alpha-(3-Methyl-1,2,3,4-Tetrahydro-8-Quinolinesulphonyl)-L-Arginyl]-2-Piperidine Carboxylic Acid (Mqpa) to Human Alpha-Thrombin: X-Ray Crystallographic Determination of the Napap-Trypsin Complex and Modeling of Napap-Thrombin and Mqpa-Thrombin Bode, W., Turk, D., Stuerzebecher, J. (1990) Eur J Biochem 193: 175
The Refined 1.9 Angstroms Crystal Structure of Human Alpha-Thrombin: Interaction with D-Phe-Pro-Arg Chloromethylketone and Significance of the Tyr-Pro-Pro-Trp Insertion Segment Bode, W., Mayr, I., Baumann, U., Huber, R., Stone, S.R., Hofsteenge, J. (1989) EMBO J 8: 3467
Organizational Affiliation: 
Max-Planck-Institut für Biochemie, Martinsried, Germany.