PROPERTIES AND CLASSIFICATION OF THE SOLUBLE ESTERASES OF HUMAN KIDNEY

Abstract

Water-soluble proteins and enzymes of human kidney were separated by vertical zone electrophoresis in starch gel and compared with those of human serum and liver. In most individuals 11 bands of proteins were detected with the aid of amido black B; some individuals had one additional band. Various substrates and inhibitors were used in efforts to identify enzymes. Five zones of esterase activity were found. One zone, characteristic of serum cholinesterase, was believed to be due to serum contained in the tissue. A zone of isozymic esterases was found to be common to both human liver and kidney and reacted like acetylesterase. Another zone, migrating at a rate approximating that of serum albumin, reacted like an aliesterase. Three small esterase bands, showing a marked hydrolysis of α-naphthyl butyrate, were found to be characteristic of renal tissue on comparison with hepatic tissue and serum. Observations on alkaline phosphatase, acid phosphatase, leucine aminopeptidase, lactic dehydrogenase, and catalase were recorded for comparison with the data on esterases.