Suzuki, Aya K. and Furukawa, Ryutaro and Sobti, Meghna and Brown, Simon H. J. and Stewart, Alastair G. and Akanuma, Satoshi and Ueno, Hiroshi and Noji, Hiroyuki (2025) Functional and structural characterization of F 1 ‐ ATPase with common ancestral core domains in stator ring. Protein Science, 34 (11). ISSN 0961-8368
Full text not available from this repository.Abstract
Abstract
Extant F 1 ‐ATPases exhibit diverse rotational stepping behaviors—3‐, 6‐, or 9‐step cycles—yet the evolutionary origin of these patterns remains unclear. Here, we used ancestral sequence reconstruction to infer the catalytic β and non‐catalytic α subunits of a putative ancestral F 1 ‐ATPase. We then fused their functionally critical domains into the thermostable F 1 from Bacillus PS3, yielding a stable chimeric enzyme. Cryo‐EM revealed two distinct conformational states—binding and catalytic dwell states—separated by a ~34° rotation of the γ subunit, suggesting a fundamental six‐step mechanism akin to that of extant six‐stepping F 1 ‐ATPases. Single‐molecule rotation assays with ATP and the slowly hydrolyzed ATP analog ATPγS demonstrated that the chimeric motor is intrinsically a six‐stepper, pausing at binding and catalytic dwell positions separated by 32.1°, although the binding dwell is significantly prolonged by an unknown mechanism. These findings indicate that F 1 ‐ATPase was originally a six‐stepper and diversified into 3‐, 6‐ and 9‐step forms in evolutionary adaptation. Based on these results, we discuss plausible features of the entire F o F 1 complex, along with potential physiological contexts in the last universal common ancestor and related lineages.
| Item Type: | Article |
|---|---|
| Subjects: | R Medicine > R Medicine (General) |
| Depositing User: | Repository Administrator |
| Date Deposited: | 22 Dec 2025 00:25 |
| Last Modified: | 22 Dec 2025 00:25 |
| URI: | http://eprints.victorchang.edu.au/id/eprint/1796 |
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