Premium
O 2 ‐Polarographic Studies on Soluble and Mitochondrial Enzymes of Crithidia fasciculata ; Glycerophosphate Enzymes *
Author(s) -
BACCHI CYRUS J.,
HUTNER S. H.,
CIACCIO E. I.,
MARCUS S. M.
Publication year - 1968
Publication title -
the journal of protozoology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.067
H-Index - 77
eISSN - 1550-7408
pISSN - 0022-3921
DOI - 10.1111/j.1550-7408.1968.tb02175.x
Subject(s) - crithidia fasciculata , biochemistry , succinate dehydrogenase , enzyme , malate dehydrogenase , mitochondrion , respiration , biology , chemistry , botany
SYNOPSIS. Mitochondrial and supernatant fractions were isolated from Crithidia fasciculata by grinding with neutral alumina and differential centrifugation. Supernatant fractions contained at least 2 NAD‐linked enzymes: an α‐glycerophosphate dehydrogenase and a malate dehydrogenase. The properties of these enzymes were investigated polarographically with phenazine ethosulfate acting as electron acceptor. Agaricic acid, cinnamic acid and p‐NO 2 ‐cinnamic acid were specific inhibitors of the α‐glycerophosphate dehydrogenase. Succinate, malate, DL‐α‐glycerophosphate and NADH stimulated respiration of mitochondrial preparations; O 2 uptake was greatest with succinate. KCN and antimycin A inhibited succinate respiration more than α‐glycerophosphate respiration. Amytal did not affect succinate, α‐glycerophosphate or NADH oxidation. The trypanocide suramin inhibited mitochondrial respiration at least 77% with each substrate. The relevance of these results to other members of the Trypanosomatidae is discussed.