Enzymatic Activity Related to Human Serum Beta-Liprotein: Histochemical, Immuno-Electrophoretic and Quantitative Studies

Abstract

Activity of 17 different enzymes was found to be present in human serum beta-lipoprotein by either standard quantitative or histochemical-immunoelectrophoretic technics. By the former methods the activity could be increased by several physical procedures which apparently affected the beta-lipoprotein molecular structure. The histochemical technics were annulled by boiling and were substrate specific except for slight reactions of the DPN dependent enzymes without substrate. Staining which occurred in these cases was more intense, however, when substrate was added. These observations suggest a possible new theory of beta-lipoprotein function: namely, that it may form a complex with enzymes as well as certain other molecules whose activity is normally intracellular thereby inactivating them while in the circulatory system.