These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Two (completely) rate-limiting steps in one metabolic pathway? The resolution of a paradox using bacteriorhodopsin liposomes and the control theory.
    Author: Westerhoff HV, Arents JC.
    Journal: Biosci Rep; 1984 Jan; 4(1):23-31. PubMed ID: 6320924.
    Abstract:
    Proton pumping by bacteriorhodopsin and charge-compensating ion movement can both and simultaneously behave as the rate-limiting step in light-driven proton uptake into bacteriorhodopsin liposomes. This apparently excessive control exerted on the net proton influx is possible because of the negative (-1) 'control coefficient' of the net proton influx with respect to the proton leaks. Furthermore, the property of bacteriorhodopsin that it is inhibited by the membrane potential is responsible for the transfer of part of the control on the net proton influx from the first, irreversible, step in the pathway (i.e. bacteriorhodopsin) to the second, reversible, step (i.e., charge-compensating ion movement).
    [Abstract] [Full Text] [Related] [New Search]