Three-dimensional Structure of Tosyl-α-chymotrypsin

  title={Three-dimensional Structure of Tosyl-$\alpha$-chymotrypsin},
  author={Brian W. Matthews and Paul B. Sigler and Richard Henderson and David M. Blow},
A model is proposed for the structure of an inhibited derivative of an enzyme which hydrolyses proteins. It is based on a map of the electron density distribution at 2 Å resolution and interpreted in terms of a previously reported sequence of 241 amino-acids. The map has been derived from a Fourier synthesis of 24,500 terms and represents two crystallographically independent molecules, each of molecular weight 25,000, which are nearly identical in their tertiary structure. The enzyme is… 
Is gamma-chymotrypsin a tetrapeptide acyl-enzyme adduct of alpha-chymotrypsin?
The crystallographic refinement provides a detailed geometrical description of the enzyme-substrate-solvent interactions that occur in the presumptive adduct and suggests that gamma-chymotrypsin may not be the free enzyme but rather a complex, possibly an acyl-enzyme adduct, with the tetrapeptide Pro-Gly-Ala-Tyr.
Structure of crystalline methyl-chymotrypsin.
2.8-A structure of yeast serine carboxypeptidase.
A surprising result of the study is that the domains consisting of residues 180-317, which form a largely alpha-helical insertion into the highly conserved cores surrounding the active site, are quite different structurally in the two molecules.
6 The Structure of Chymotrypsin
Gamma-chymotrypsin is a complex of alpha-chymotrypsin with its own autolysis products.
HPLC analyses of the enzyme before and after crystallization demonstrated the presence of a wide variety of oligopeptides in the redissolved crystal, most with COOH-terminal aromatic residues, as expected of the products of chymotrypsin cleavage.


Tertiary Structure of Ribonuclease
A model is proposed of the polypeptide chain in bovine pancreatic ribonuclease based on a 2 Å electron density map involving 7,294 reflexions and data from seven heavy atom derivatives. The molecule
Corrections to the amino acid sequence of bovine chymotrypsinogen A.
Reinvestigation of the amino acid sequence of bovine chymotrypsinogen A suggests that the amino acid sequence at the N-terminus of the B-chain (residues 16-19) is -Ile-Val-Asn-Gly- rather than
An X-Ray Study of Chymotrypsin and Hæmoglobin
We have recently been fortunate in obtaining well-developed crystals of two proteins—chymo-trypsin and haemoglobin. The former were prepared for us by Dr. Northrop of Princeton and the latter
A mathematical model-building procedure for proteins
to be 0.112 A shorter than the sum of the Pauling covalent radii for carbon and sulphur. This bond must therefore possess considerable double-bond character. Cucka (1963) also puts forward an
The accurate determination of the position and shape of heavy‐atom replacement groups in proteins
Green, Ingrain & Perutz (1954) introduced the method of isomorphous replacement with heavy atoms to the X-ray analysis of the centro-symmetric zone of horse haemoglobin. In order to determine the
A least‐squares analysis of the diffuse X‐ray scattering from carbons
The theoretical x-ray intensities scattered from perfectly regular, condensed, aromatic molecules of various sizes have been presented previously in numerical form. A matrix method is described
Structure of Hen Egg-White Lysozyme: A Three-dimensional Fourier Synthesis at 2 Å Resolution
Structure of Hen Egg-White Lysozyme: A Three-dimensional Fourier Synthesis at 2 A Resolution