[A mechanism of mononucleotide formation under endonuclease hydrolysis].

It has been shown under poly-A hydrolysis by endonuclease A236 in the presence of large amounts of E. coli phosphatase that the formation of mononucleotides requires the presence of terminal 5'-P in the substrate. Simultaneously, it has been found for endonuclease A236 and nuclease of Serratia marcescens that the products of exhaustive hydrolysis carried out in the presence of excess amounts of phosphatase contain an additional nucleoside residue as compared to the ordinary products of exhaustive hydrolysis, the number of phosphate groups being equal in both cases.