[Regulatory mechanism of the cytoplasmic pH by H(+)-adenosinetriphosphatase]

Nature prefers simplicity. Streptococcal cytoplasmic pH is regulated in a simple biological manner: change in the amount of the adenosinetriphosphatase (H(+)-ATPase). This enzyme is identical to the F0F1-complex of oxidative phosphorylation, which synthesizes adenosinetriphosphate in mitochondria and most of bacteria, whereas it is used as a regulator of the cytoplasmic pH in streptococci which have no respiratory chain. Eukaryotes use the another type of H(+)-ATPase to regulate the internal pH. Thus, the evolutional process of H(+)-ATPase is quite interesting.