AMINO ACID AND METAL COMPOSITION OF THE α- AND β-LYTIC PROTEASES OF SORANGIUM SP.

Abstract

Amino acid compositions of two enzymes, α- and β-lytic proteases of Sorangium sp., are reported. The calculated molecular weights and nitrogen contents are in good agreement with experimental values reported previously. A method is described for computing a "best estimate" of the multiplier which converts composition per unit weight of enzyme preparation to composition per mole of enzyme. According to analyses of the performate-oxidized enzymes and of the carboxymethylated enzymes, the α-enzyme has six and the β-enzyme has four half-cystine residues. Titratable sulfhydryl groups could not be detected in either enzyme. The β-enzyme contains one atom of zinc; removal of zinc with o-phenanthroline did not release a titratable sulfhydryl group.