Interrelationships between Growth Yield, ATPase and Adenylate Kinase Activities in Zymomonas mobilis

Abstract

The presence of cytoplasmic and membrane-bound adenylate kinase (EC 2.7.4.3) as well as inorganic pyrophosphatase (EC 3.6.1.1) was detected in Zymomonas mobilis ATCC 29191. An increase in the molar growth yield (YX/S) of Z. mobilis under aerobic growth conditions appeared to be in proportion to a reduction of membrane-bound adenylate kinase (mAK) and ATPase activities and to an increase in cytoplasmic adenylate kinase (AK) activity. Significant (1 — P < 0.01) multiple regressions were observed between the values of YX/S (dependent variable), ATPase and AK or AK and mAK as independent variables, suggesting that a combined operation of these phosphohydrolases and phosphotransferases would be responsible for the biomass yield in Z. mobilis.