METABOLISM OF MUCOPOLYSACCHARIDES IN CONNECTIVE TISSUE. II. SYNTHESIS OF GLUCOSAMINE-6-PHOSPHATE *

Abstract

The transamidase which synthesizes glucosamine-6-phosphate and the glutamic-oxaloacetic and glutamic-pyruvic transaminases were studied in connective tissue and liver of rats, and in human synovial tissue. Cortisol was found to cause a moderate diminution in the activity of the fructose-6-phosphate-glutamine transamidase, but caused an increase in the glutamic-oxaloacetic transaminase activity of connective tissue homogenates. No change in the glutamic-pyruvic transaminase activity occurred. In the liver, cortisol administration caused a moderate decrease in fructose-6-phosphate-glutamine transamidase activity and marked increase in glutamic-oxaloacetic and glutamic-pyruvic transaminase activities. Gold chloride inhibited the activity of the transamidase which synthesizes glucosamine-6-phosphate in connective tissue homogenates in vitro in concentrations which are found in the serum of patients receiving gold compounds therapeutically. Gold sodium thiomalate administration in vivo resulted in decrease in the activity of this enzyme in connective tissue but not in liver.