Open AccessThe Oxidation of Malate and Exogenous Reduced Nicotinamide Adenine Dinucleotide by Isolated Plant Mitochondria
Author(s) -
David A. Day,
Joseph T. Wiskich
Publication year - 1974
Publication title -
plant physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.554
H-Index - 312
eISSN - 1532-2548
pISSN - 0032-0889
DOI - 10.1104/pp.53.1.104
Subject(s) - antimycin a , nad+ kinase , rotenone , biochemistry , mitochondrion , malate dehydrogenase , nicotinamide adenine dinucleotide , malonate , chemistry , biology , enzyme
Exogenous NADH oxidation by cauliflower (Brassica oleracea L.) bud mitochondria was sensitive to antimycin A and gave ADP/O ratios of 1.4 to 1.9. In intact mitochondria, NADH-cytochrome c reductase activity was only slightly inhibited by antimycin A. The antimycin-insensitive activity was associated with the outer membrane. Malate oxidation was sensitive to both rotenone and antimycin A and gave ADP/O values of 2.4 to 2.9. However in the presence of added NAD(+), malate oxidation displayed similar properties to exogenous NADH oxidation. In both the presence and absence of added NAD(+), malate oxidation was dependent on inorganic phosphate and inhibited by 2-n-butyl malonate.