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Hydrogenosome-localization of arginine deiminase in Trichomonas vaginalis.

ABSTRACT: The arginine dihydrolase (ADH) pathway has an analogous function to the urea cycle in mitochondria-containing cells, by removing nitrogen from amino acids and generating ATP. Subcellular localization of the ADH pathway enzymes in Trichomonas vaginalis revealed that arginine deiminase (ADI) localizes to the hydrogenosome, a mitochondrion-like organelle of anaerobic protists. However the other enzymes of the ADH pathway, ornithine carbamyltransferase and carbamate kinase localize to the cytosol. Three gene sequences of T. vaginalis ADI (ADI 1-3) were identified in the T. vaginalis genome, all having putative mitochondrial targeting sequences. The ADI sequences were cloned and used to probe T. vaginalis using a carboxyterminal di-hemogglutinin epitope tag which demonstrated co-localization with malic enzyme confirming the hydrogenosome localization of this enzyme.

SUBMITTER: Morada M

PROVIDER: S-EPMC3026898 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Hydrogenosome-localization of arginine deiminase in Trichomonas vaginalis.

Morada Mary M Smid Ondrej O Hampl Vladimir V Sutak Robert R Lam Brian B Rappelli Paola P Dessì Daniele D Fiori Pier L PL Tachezy Jan J Yarlett Nigel N

Molecular and biochemical parasitology 20101111 1

The arginine dihydrolase (ADH) pathway has an analogous function to the urea cycle in mitochondria-containing cells, by removing nitrogen from amino acids and generating ATP. Subcellular localization of the ADH pathway enzymes in Trichomonas vaginalis revealed that arginine deiminase (ADI) localizes to the hydrogenosome, a mitochondrion-like organelle of anaerobic protists. However the other enzymes of the ADH pathway, ornithine carbamyltransferase and carbamate kinase localize to the cytosol. T ...[more]

PMID: 21074581

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