Structural Studies of Bovine Liver Rhodanese
Year: 1971
Type: article
Abstract: Crystalline bovine liver rhodanese, prepared by ammonium sulfate and pH precipitation, has been shown to be comprised of two fully active components present in approximately equal amounts which are separable by polyacrylamide gel electrophoresis and by ion exchange chromatography. The two rhodanese forms, designated A and B on the basis of their order of elution from columns of DEAE-Sephadex, are not in equilibrium nor do they represent free enzyme and an enzyme-substrate complex. Furthermore, the two rhodanese species are identical with respect to kinetic parameters, amino acid composition, NH2-terminal amino acid, sulfhydryl content, tryptic peptide maps, and molecular weight. Both forms exhibit equal activity toward β-mercaptopyruvate and utilize this sulfur donor at an efficiency of about 1% that of thiosulfate. Although no chemical or physical basis for the difference between the two rhodanese forms has been found as yet, a new, milder method for the preparation of the enzyme yields a preponderance of rhodanese A (85 to 90%). This, considered together with the elution characteristics of rhodaneses A and B, suggests that rhodanese B may arise during the course of the purification by deamidation of the A form.
Source: Journal of Biological Chemistry
Institution: University of Chicago
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,430
OpenAlex ID: W1505275687