Open AccessSubcellular localization of glutamate dehydrogenases and alanine aminotransferase in epimastigotes of Trypanosoma cruzi
Author(s) -
Duschak Vilma Gladys,
Cazzulo Juan José
Publication year - 1991
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1991.tb04429.x-i1
Subject(s) - glutamate dehydrogenase , biochemistry , nad+ kinase , subcellular localization , alanine , biology , cytosol , digitonin , cell fractionation , mitochondrion , enzyme , differential centrifugation , microbiology and biotechnology , glutamate receptor , amino acid , cytoplasm , receptor
The subcellular localization of NAD‐ and NADP‐linked glutamate dehydrogenases (GDH‐NAD and GDH‐NADP), alanine aminotransferase (ALAT) and aspartate aminotransferase (ASAT) in epimastigotes of Trypanosoma cruzi was studied by digitonin extraction from whole cells, subcellular fractionation by differential centrifugation. A and isopycnic ultracentrifugation. All enzymes presented both a cytosolic and a mitochondrial form; in addition, GDH‐NADP seems to have a third, still undefined, localization. The results are compatible with the existence of two pathways for the production of l ‐alanine linked to the reoxidation of glycolytic NADH, one operative in the mitochondrion and the other in the cytosol, and perhaps responsible for the existence of the two alanine pools detected by 13 C‐nuclear magnetic resonance (B. Frydman et al., Eur. J. Biocbem. 192 (1990) 363–368).