ATP synthesis-coupled and -uncoupled acetate production from acetyl-CoA by mitochondrial acetate:succinate CoA-transferase and acetyl-CoA thioesterase in Trypanosoma.

ABSTRACT: Insect stage trypanosomes use an "acetate shuttle" to transfer mitochondrial acetyl-CoA to the cytosol for the essential fatty acid biosynthesis. The mitochondrial acetate sources are acetate:succinate CoA-transferase (ASCT) and an unknown enzymatic activity. We have identified a gene encoding acetyl-CoA thioesterase (ACH) activity, which is shown to be the second acetate source. First, RNAi-mediated repression of ASCT in the ACH null background abolishes acetate production from glucose, as opposed to both single ASCT and ACH mutants. Second, incorporation of radiolabeled glucose into fatty acids is also abolished in this ACH/ASCT double mutant. ASCT is involved in ATP production, whereas ACH is not, because the ASCT null mutant is ∼1000 times more sensitive to oligomycin, a specific inhib

SUBMITTER: Millerioux Y 

PROVIDER: S-EPMC3366814 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature