Purification and Properties of Ribose-Phosphate Isomerase from <em>Candida utilis</em>.

The purification of ribose-5-phosphate isomerase from Candida utilis is described. The procedure used extends over six steps to a 27% yield of a homogeneous protein. The following properties have been elucidated: the enzyme has a molecular weight of 105000 and will dissociate into four subunits upon the addition of sodium dodecylsulfate. The specific activity is about 350 international units per mg protein. The pH optimum, Km for ribose-5-phosphate, amino acid composition and isoelectric point have been determined. The isomerase is extremely sensitive to organic mercurials. [ABSTRACT FROM AUTHOR]