Distribution of phosphatases in human erythrocytes

The Phosphatases of Human Erythrocytes

By HELEN QUINCY WOODARD, PH.D. V ARIOUS investigatorst5 have reported that erythrocytes exhibit phosphatase activity at pH values between 4 and 6, and some believe that this is due to two acid phosphatases with maximum activities at about pH 4.2. and .6. Reports on alkaline phosphatase activity have been less numerous.’ ‘ 6 , 7 In the course of an investigation of the glycerophosphatase activit...

Kinetic comparison of genetically different acid phosphatases of human erythrocytes.

The distribution of zinc in human erythrocytes.

Gel permeation chromatography was used to fractionate zinc-bound constituents in haemolysates of human blood samples. The zinc content of the fractions was determined by electrothermal atomic absorption spectrometry. The zinc-containing enzyme, carbonic anhydrase, was identified by isoelectric focusing. A fraction of more than 0.9 of the zinc eluted from the column was bound to the carbonic anh...

Calcium distribution within human erythrocytes.

In order to study 45Ca distribution within erythrocytes, a method was devised that had minimal deleterious effects on the treated erythrocytes. It was observed that newly introduced 45Ca was predominantly recoverable from the cytosol and exchanged relatively slowly with membrane-associated Ca. Younger erythrocytes appeared to have relatively more 45Ca in membrane-associated sites. Erythrocytes ...

Calcium distribution within human erythrocytes during endocytosis.

In order to study 45Ca movements within erythrocytes, a method was devised that had minimal deleterious effect on the treated erythrocytes. Agents that induce endocytosis in intact erythrocytes (primaquine, vinblastine, and chlorpromazine) caused a prompt movement of 45Ca from cytosol to membrane-associated sites. This drug-induced movement of 45Ca to membrane sites was blocked by depleting ery...