Energy capture and use in plants and bacteria. Final technical report
The project has centered on elucidation of the mechanism of ATP synthase. The metabolic importance of ATP and the complexity of the ATP synthase have made the problem particularly important and challenging. The development of the binding change mechanism depended upon our recognition of features that were novel in bioenergetics and indeed to the field of enzymology. One important feature of mechanism is that the principal way that energy input from transmembrane proton movement is coupled to ATP formation is to drive conformational changes that cause the release of ATP readily formed and tightly bound at a catalytic site. Another is that three equivalent catalytic sites on the enzyme show strong catalytic cooperativity as they proceed sequentially through different conformations. A more speculative features is that this cooperativity and energy coupling involve a rotational movement of minor subunits relative to the catalytic subunits. During this period these studies have extended and clarified aspects of the synthase mechanism. During assessments of interactions of Mg{sup 2+} and ADP with the synthase we recognized unexpectedly that whether ADP and P{sub i}, or their complexes with Mg{sup 2+} served as substrates for ATP formation by photophosphorylation was not known. Our studies showed that MgADP and free P{sub i} act as substrates.
- Research Organization:
- Univ. of California, Los Angeles, CA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- FG03-88ER13845
- OSTI ID:
- 10163235
- Report Number(s):
- DOE/ER/13845-T3; ON: DE94014592; BR: KC0600000
- Resource Relation:
- Other Information: PBD: [1993]
- Country of Publication:
- United States
- Language:
- English
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