Open AccessCortisol Modification of HeLa 65 Alkaline Phosphatase
Author(s) -
BAZZELL Kirstan L.,
PRICE Gary,
TU Sylvia,
GRIFFIN Martin,
COX Rody,
GHOSH Nimai
Publication year - 1976
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1976.tb10044.x
Subject(s) - alkaline phosphatase , enzyme , phosphatase , chemistry , biochemistry , hela , acid phosphatase , phosphate , phosphoprotein , enzyme assay , sialic acid , phosphorylation , cell
Alkaline phosphatase activity of HeLa cells is increased 5–20‐fold during growth in medium with cortisol. The increase in enzyme activity is due to an enhanced catalytic efficiency rather than an increase in alkaline phosphatase protein in induced cells. In the present study the chemical composition of control and induced forms of alkaline phosphatase were investigated to determine the enzyme modification that may be responsible for the increased catalytic activity. HeLa alkaline phosphatase is a phosphoprotein and the induced form of the enzyme has approximately one‐half of the phosphate residues associated with control enzyme. The decrease in phosphate residues of the enzyme apparently alters its catalytic activity. Other chemical components of purified alkaline phosphatase from control and induced cells are similar; these include sialic acid, hexosamine and sulfhydryl residues.