[Regulation of glucosamine synthetase activity by cholesterol and hydrocortisone]

The effects of cholesterol and hydrocortisone (cortisol) on the activity of purified glucosamine synthetase from rat liver was studied in vitro. It was found that the enzyme activity is increased by cholesterol and inhibited by hydrocortisone. These steroids block the allosteric effect of vitamin K1 on the enzyme. There is evidence testifying to the allosteric type of cholesterol and hydrocortisone effects on glucosamine synthetase.