[en] A pencillin-sensitive enzyme, the exocellular DD-carboxypeptidase-transpeptidase from Streptomyces R61, has been crystallized from polyethylene glycol (Mr = 6000 to 7500) solution at pH 7•6. X-ray examination of the orthorhombic crystals shows the space group is P212121, with unit cell dimensions a = 51•1 Å, B = 67•4 Å, and C = 102•9 Å. With four molecules of molecular weight 38,000, the Å3/dalton ratio for the cell is 2•33. The crystals are stable to irradiation for 75 hours and are suitable for structure analysis to at least 2•4 Å resolution. The radius of gyration of the molecule in solution at pH 6.8 is 20.8 Å.
Frére, Ghuysen, Perkins, Nieto (1973) Molecular weight and amino acid composition of the exocellular DD-carboxypeptidase-transpeptidase of Streptomyces R61. Biochem J 135:463-468.
Ghuysen, Leyh-Bouille, Frére, Dusart, Marquet, Perkins, Nieto Ann. New York Acad. Sci 1974, 235:236-268.
Ghuysen, Frére, Leyh-Bouille, Coyette, Dusart, Nguyen-Distéche (1979) Use of model enzymes in the determination of the mode of action of penicillins and delta 3-cephalosporins. Annu Rev Biochem, In the press; .
Knox, Kelly, Moews, DeLucia Microbial Drug Resistance , S. Mitsuhashi, University of Tokyo Press, Tokyo; 1978, 2.
