Abstract
UDPG pyrophosphorylase (UTP: α- d-glucose-1-phosphate uridylyltransferase, E.C. 2.7.7.9) isolated from rat sublingual and submandibular glands, is similar to that from liver and is located in cytoplasm (80 per cent) and in the nuclear fraction (20 per cent). DEAE-cellulose chromatography of the extracts isolated two forms of the enzyme from liver but only one from the salivary glands. The uridylyltransferase from all 3 tissues showed high specificity for UTP as substrate. The enzyme activity was inhibited by the two reaction products, PP i and UDPG. Mg 2+ and Mn 2+ enhanced the enzyme activity, whereas Ni 2+ and Cd 2+ inhibited it. Co 2+ did not affect the enzyme from liver, caused 2-fold enhancement of the activity of the enzyme from the sublingual gland and inhibited the submandibular gland enzyme. The differences in the effect of cobalt ion can be taken advantage of for differentiation of the enzymes. The molecular weight of the enzyme from all 3 tissues was about 300,000.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
