title: Acetate:succinate CoA-transferase in the hydrogenosomes of Trichomonas vaginalis: identification and characterization.
abstract: Acetate:succinate CoA-transferases (ASCT) are acetate-producing enzymes in hydrogenosomes, anaerobically functioning mitochondria and in the aerobically functioning mitochondria of trypanosomatids. Although acetate is produced in the hydrogenosomes of a number of anaerobic microbial eukaryotes such as Trichomonas vaginalis, no acetate producing enzyme has ever been identified in these organelles. Acetate production is the last unidentified enzymatic reaction of hydrogenosomal carbohydrate metabolism. We identified a gene encoding an enzyme for acetate production in the genome of the hydrogenosome-containing protozoan parasite T. vaginalis. This gene shows high similarity to Saccharomyces cerevisiae acetyl-CoA hydrolase and Clostridium kluyveri succinyl-CoA:CoA-transferase. Here we demonstrate that this protein is expressed and is present in the hydrogenosomes where it functions as the T. vaginalis acetate:succinate CoA-transferase (TvASCT). Heterologous expression of TvASCT in CHO cells resulted in the expression of an active ASCT. Furthermore, homologous overexpression of the TvASCT gene in T. vaginalis resulted in an equivalent increase in ASCT activity. It was shown that the CoA transferase activity is succinate-dependent. These results demonstrate that this acetyl-CoA hydrolase/transferase homolog functions as the hydrogenosomal ASCT of T. vaginalis. This is the first hydrogenosomal acetate-producing enzyme to be identified. Interestingly, TvASCT does not share any similarity with the mitochondrial ASCT from Trypanosoma brucei, the only other eukaryotic succinate-dependent acetyl-CoA-transferase identified so far. The trichomonad enzyme clearly belongs to a distinct class of acetate:succinate CoA-transferases. Apparently, two completely different enzymes for succinate-dependent acetate production have evolved independently in ATP-generating organelles.
authors.affiliation: Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 2, 3584 CM Utrecht, The Netherlands.
authors.forename: Koen W A
authors.initials: KWA
authors.lastname: van Grinsven
authors.affiliation: Institute of Botany III, Heinrich Heine University, Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.
authors.forename: Silke
authors.initials: S
authors.lastname: Rosnowsky
authors.affiliation: Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 2, 3584 CM Utrecht, The Netherlands.
authors.forename: Susanne W H
authors.initials: SWH
authors.lastname: van Weelden
authors.affiliation: Institute of Botany III, Heinrich Heine University, Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.
authors.forename: Simone
authors.initials: S
authors.lastname: Pütz
authors.affiliation: Centre for Eukaryotic Evolutionary Microbiology, School of Biosciences, University of Exeter, Stocker Road, Exeter EX4 4QD, United Kingdom.
authors.forename: Mark
authors.initials: M
authors.lastname: van der Giezen
authors.affiliation: Institute of Botany III, Heinrich Heine University, Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.
authors.forename: William
authors.initials: W
authors.lastname: Martin
authors.affiliation: Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 2, 3584 CM Utrecht, The Netherlands; Department of Medical Microbiology & Infectious Diseases, ErasmusMC University Medical Center, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands.
authors.forename: Jaap J
authors.initials: JJ
authors.lastname: van Hellemond
authors.affiliation: Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 2, 3584 CM Utrecht, The Netherlands; Department of Medical Microbiology & Infectious Diseases, ErasmusMC University Medical Center, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands.
authors.forename: Aloysius G M
authors.initials: AGM
authors.lastname: Tielens
authors.affiliation: Institute of Botany III, Heinrich Heine University, Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany. Electronic address: katrin.henze@uni-duesseldorf.de.
authors.forename: Katrin
authors.initials: K
authors.lastname: Henze
mesh_terms: D000085:Acetates / Q000378:metabolism; D000105:Acetyl Coenzyme A / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology; D000918:Antibody Specificity; D016466:CHO Cells; D002852:Chromatography, Ion Exchange; D015256:Coenzyme A-Transferases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D006224:Cricetinae; D003412:Cricetulus; D017125:Genes, Protozoan; D007700:Kinetics; D008969:Molecular Sequence Data; D015388:Organelles / Q000201:enzymology*; D010455:Peptides / Q000737:chemistry; D021381:Protein Transport; D011994:Recombinant Proteins / Q000378:metabolism; D016415:Sequence Alignment; D013347:Subcellular Fractions / Q000201:enzymology; D019802:Succinic Acid / Q000378:metabolism; D014246:Trichomonas vaginalis / Q000201:enzymology* / Q000235:genetics
chemical_list: D000085:Acetates; D000913:Antibodies, Protozoan; D010455:Peptides; D011994:Recombinant Proteins; D000105:Acetyl Coenzyme A; D019802:Succinic Acid; D015256:Coenzyme A-Transferases; C049804:acetate-succinate CoA-transferase