Transport of coenzyme A in plant mitochondria.
Oxoglutarate oxidation by purified potato mitochondria which had been stored at low temperature for 48 h or longer was stimulated by added coenzyme A. Exogenous coenzyme A was accumulated by potato mitochondria, both freshly prepared and aged, in a manner sensitive to uncouplers and low temperature. Coenzyme A was concentrated approximately 10-fold in the matrix under steady-state conditions. This coenzyme A uptake followed saturation kinetics with an apparent Km of 0.2 mM and a V of 4-6.5 nmol min-1 mg-1 protein, suggesting carrier-mediated transport. This transport was insensitive to an inhibitor of NAD+ transport. It is suggested that plant mitochondria possess a specific carrier for the net accumulation of coenzyme A.
D001693:Biological Transport, Active; D003065:Coenzyme A / Q000378:metabolism* / Q000494:pharmacology; D007656:Ketoglutaric Acids / Q000378:metabolism; D007700:Kinetics; D008928:Mitochondria / Q000378:metabolism*; D009243:NAD / Q000378:metabolism; D010084:Oxidation-Reduction; D010101:Oxygen Consumption / Q000187:drug effects; D010944:Plants / Q000648:ultrastructure*; D014675:Vegetables
D007656:Ketoglutaric Acids; D009243:NAD; D003065:Coenzyme A