Sedimentation Behavior of Serum Lactic Dehydrogenase

Abstract

Lactic dehydrogenase (LDH) from: (a) serum of an apparently healthy individual; (b) sera from 2 patients with myelogenous leukemia; and (c) lysed erythrocytes, behaved essentially as a monodisperse compound, sedimenting at a rate which is in good agreement with that reported for the crystalline enzyme obtained from other sources. A major portion of the LDH activity of cancer serum was associated with a single com-ponent having a sedimentation constant (s20,w) of 6.71 x 10-13. Normal serum and lysed ervthrocytes gave similar results with s20 w values of 7.09 x 10-13 and 7.32 x 10-13, respectively.