Formation of Adenosine Cyclic 3′,5′-Phosphate by Nonproliferating Cells and Cell-free Extract of Brevibacterium liquefaciens

Abstract

The formation of adenosine cyclic 3′,5′-phosphate by Brevibacterium liquefaciens ATCC 14929 was studied with the use of nonproliferating cells and cell-free extract. With nonproliferating cells provided by deprivation of sulfate, the formation of this nucleotide was accelerated by adding some amino acids and sugars. Among amino acids tested, alanine and asparagine were most effective. Pentoses were more favorable than hexoses and other sugars. Formation of adenosine cyclic 3′,5′-phosphate was observed also with chloramphenicol-treated cells. Experiments on cell-free extract showed that addition of alanine or pyruvate stimulated the formation of adenosine cyclic 3′,5′-phosphate from adenosine-5′-triphosphate. When alanine was added to the cell-free system, shaking of the reaction mixture further increased the amount of the nucleotide, but pyruvate was far more effective than alanine. No synergistic effect of alanine and pyruvate was observed. Some enzyme activity was observed which decomposed adenosine cyclic 3′,5′-phosphate, but it was weak as compared with adenyl cyclase activity in the presence of pyruvate. From the results obtained, it appears that pyruvate may act as an activating factor of adenyl cyclase in Brevibacterium liquefaciens .