An intermediate in the biosynthesis of insulin has been isolated from anglerfish islets and shown to have the structure of insulin with the additional amino acid residues GlyThr-Lys attached to the NH2 terminus of the A chain. This intermediate can be produced in vitro by a rapid tryptic enzymic cleavage of anglerfish proinsulin; more extensive trypsin treatment converts this intermediate to in...

Cells signal through lipids produced by phospholipid and phosphoinositide metabolism that involves three enzymic processes: (i) ester and phosphodiester hydrolysis by phospholipases; (ii) monophosphate hydrolysis by phosphatases; and (iii) phosphorylation of hydroxy groups by kinases. Unregulated enzyme activity correlates with specific pathologies, which are specific targets for therapeutic in...

The method, here presented, is based on the findings of Moore and Stein (1) who have shown that, over a broad range, the color produced by the interaction of an improved ninhydrin reagent with a large number of amino acids and peptides conforms with Beer’s law, although all amino acids and peptides do not produce equal color yields. This procedure has been found to be relatively simple, reasona...

H. A. KREBS, P. K. JENSEN AND L. V. EGGLESTON I958 3. Adenosine 5'-phosphate, L-aspartate, L-asparagine, fumarate and glycerol each stimulated 'factor' activity but had no effect on the enzymic hydrolysis ofcarbamyl phosphate. This stimulation generally increased with time. 4. Some characteristics ofthe bacterial hydrolysis of carbamyl phosphate are described. 5. The results indicate that the b...