Work

ATP Synthase with Its γ Subunit Reduced to the N-terminal Helix Can Still Catalyze ATP Synthesis

Year: 2009

Type: article

Abstract: ATP synthase uses a unique rotary mechanism to couple ATP synthesis and hydrolysis to transmembrane proton translocation. As part of the synthesis mechanism, the torque of the rotor has to be converted into conformational rearrangements of the catalytic binding sites on the stator to allow synthesis and release of ATP. The gamma subunit of the rotor, which plays a central role in the energy conversion, consists of two long helices inside the central cavity of the stator cylinder plus a globular portion outside the cylinder. Here, we show that the N-terminal helix alone is able to fulfill the function of full-length gamma in ATP synthesis as long as it connects to the rest of the rotor. This connection can occur via the epsilon subunit. No direct contact between gamma and the c ring seems to be required. In addition, the results indicate that the epsilon subunit of the rotor exists in two different conformations during ATP synthesis and ATP hydrolysis.

Source: Journal of Biological Chemistry

DOI: 10.1074/jbc.m109.030528

Authors: Nelli Mnatsakanyan, Jonathon A. Hook, Leah Quisenberry, Joachim Weber

Institutions: Texas Tech University, Texas Tech University Health Sciences Center

Language: English

Topic: ATP Synthase and ATPases Research

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: hybrid

Estimated APC paid: $3,430

Funders: Texas Tech University, National Institutes of Health, National Institute of General Medical Sciences