Regulatory Mechanisms and Environmental Adaptation of the F-ATPase Family.

Abstract

The F-type ATPase family of enzymes, including ATP synthases, are found ubiquitously in biological membranes. ATP synthesis from ADP and inorganic phosphate is driven by an electrochemical H+ gradient or H+ motive force, in which intramolecular rotation of F-type ATPase is generated with H+ transport across the membranes. Because this rotation is essential for energy coupling between catalysis and H+-transport, regulation of the rotation is important to adapt to environmental changes and maintain ATP concentration. Recently, a series of cryo-electron microscopy images provided detailed insights into the structure of the H+ pathway and the multiple subunit arrangement. However, the regulatory mechanism of the rotation has not been clarified. This review describes the inhibition mechanism of ATP hydrolysis in bacterial enzymes. In addition, properties of the F-type ATPase of Streptococcus mutans, which acts as a H+-pump in an acidic environment, are described. These findings may help in the development of novel antimicrobial agents.