In the mitochondrial oxidative phosphorylation system, the energy from the oxidative reactions is used for the generation of a H ion-gradient and associated membrane potential which subsequently drives the phosphorylation of ADP by Pi. Pi-ATP exchange, which is a part of the ADP phosphorylation reaction, is catalyzed by the vesicular energy transducing ATPase complex. Recent work from the laboratory has led to the identification of coupling factor B, a 15,000 dalton -SH containing protein, as a component of the Pi-ATP exchange activity catalyzed by the ATPase complex. The factor is not needed for the oligomycin sensitive ATPase activity. We propose to determine the location of the factor in the membrane - whether it is on the inner or outer surface of the inner mitochondrial membrane. Secondly, we will examine the effect of Factor B in depleted submitochondrial particles on the H ion-uptake associated with ATP breakdown and subsequent relaxation of the gradient due to leakage.
A third aim will be to look for other functionally important groups in the protein using protein modifying agents.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
3R01GM013641-18S1
Application #
3268528
Study Section
Physical Biochemistry Study Section (PB)
Project Start
1977-07-01
Project End
1986-06-30
Budget Start
1985-09-23
Budget End
1986-06-30
Support Year
18
Fiscal Year
1985
Total Cost
Indirect Cost
Name
Boston Biomedical Research Institute
Department
Type
DUNS #
058893371
City
Watertown
State
MA
Country
United States
Zip Code
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