Regulation of cytosol 5′-nucleotidase by adenylate energy charge

摘要: Abstract In the physiological range of adenylate energy charge in liver (0.7–0.9), rate AMP-hydrolysis catalyzed by rat cytosol 5′-nucleotidase (5′-ribonucleotide phosphohydrolase, EC 3.1.3.5) increased sharply with decreasing charge. addition, a decrease concentration P i caused marked acceleration AMP-hydrolysing activity over These responses seem to serve protect cells against metabolic stress which could result from sudden utilization ATP removal AMP. The this enzyme decreased as size adenine nucleotide pool range. This effect may be self-limiting response prevent excess depletion pool. IMP-hydrolysing increasing But no its variation within was observed. On basis data obtained study, seems comparable that AMP deaminase reaction, but estimated less than 10% reaction at value about 0.7. strongly suggests → IMP inosine pathway is more significant adenosine liver.