Biosynthesis of intestinal mucins. 3. Formation of ‘active sulphate’ by cell-free extracts of sheep colonic mucosa

Abstract

Supernatant enzyme fractions from sheep colonic mucosa catalyze the formation of an "active sulfate" from adenosine triphosphate and SO4[long dash]ions. The "active sulfate" has been isolated and found to be an adenine nucleotide carrying a very labile sulfate ester. The compound is identical with or closely similar to adenosine 3[image]-phosphate 5[image]-phosphosulfate. The "active sulfate" acts as donor in the formation of phenolic sulfates by liver or mucosal enzymes. No evidence for the sulfation of simple mono- and di-saccharides could be obtained. Mucosal enzymes catalyze breakdown of adenosine triphosphate to inosine, inosine monophosphate and hypoxanthine.