L-arginine uptake and L-phosphoarginine synthesis in Trypanosoma cruzi

A very specific L-arginine transporter showing high affinity has been characterized in Trypanosoma cruzi epimastigotes. Uptake was found to be dependent on L-arginine concentration and it was saturable. Values for maximum velocity and Km ranged between 48.1-57.5 pmol·min-1 per 3 x 107 cells and betw...

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Autores principales:	Pereira, C.A., Alonso, G.D., Paveto, M.C., Flawiá, M.M., Torres, H.N.
Formato:	JOUR
Materias:	Amino acid transport Arginine kinase Canavanine Epimastigotes Homoarginine Phosphagen amino acid synthesis amino acid transport arginine canavanine citrulline energy metabolism homoarginine microbe metabolism ornithine phosphoarginine Trypanosoma Trypanosoma cruzi
Acceso en línea:	http://hdl.handle.net/20.500.12110/paper_10665234_v46_n6_p566_Pereira
Aporte de:	Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires

id	todo:paper_10665234_v46_n6_p566_Pereira
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spelling	todo:paper_10665234_v46_n6_p566_Pereira2023-10-03T16:02:07Z L-arginine uptake and L-phosphoarginine synthesis in Trypanosoma cruzi Pereira, C.A. Alonso, G.D. Paveto, M.C. Flawiá, M.M. Torres, H.N. Amino acid transport Arginine kinase Canavanine Epimastigotes Homoarginine Phosphagen amino acid synthesis amino acid transport arginine canavanine citrulline energy metabolism homoarginine microbe metabolism ornithine phosphoarginine Trypanosoma Trypanosoma cruzi Trypanosoma cruzi A very specific L-arginine transporter showing high affinity has been characterized in Trypanosoma cruzi epimastigotes. Uptake was found to be dependent on L-arginine concentration and it was saturable. Values for maximum velocity and Km ranged between 48.1-57.5 pmol·min-1 per 3 x 107 cells and between 4.2-5.5 μM, respectively The calculated activation energy and Q10 were 31.1 KJ·mol-1, and 1.7, respectively. Uptake velocity significantly increased when cells were preincubated in the absence of L-arginine. Cells retained the labeled amino acid independently of the presence or absence of exogenous L-arginine. The specificity of L-arginine uptake was demonstrated by competition assays in the presence of 80-fold molar excess of natural amino acids and several L-arginine derivatives. The highest levels of inhibition were caused by L-homoarginine. D-arginine, L-canavanine, L-ornithine, and L-citrulline, L-arginine uptake by T. cruzi epimastigotes was not affected by the presence of potassium or sodium ions in the incubation mixture or by pH changes in the range between 5.5-8.5. The major product of L-arginine uptake was characterized as phosphoarginine. Moreover, arginine kinase activity was detected in soluble extracts from T. cruzi epimastigotes. Fil:Pereira, C.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Alonso, G.D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Paveto, M.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Flawiá, M.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Torres, H.N. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_10665234_v46_n6_p566_Pereira
institution	Universidad de Buenos Aires
institution_str	I-28
repository_str	R-134
collection	Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic	Amino acid transport Arginine kinase Canavanine Epimastigotes Homoarginine Phosphagen amino acid synthesis amino acid transport arginine canavanine citrulline energy metabolism homoarginine microbe metabolism ornithine phosphoarginine Trypanosoma Trypanosoma cruzi Trypanosoma cruzi
spellingShingle	Amino acid transport Arginine kinase Canavanine Epimastigotes Homoarginine Phosphagen amino acid synthesis amino acid transport arginine canavanine citrulline energy metabolism homoarginine microbe metabolism ornithine phosphoarginine Trypanosoma Trypanosoma cruzi Trypanosoma cruzi Pereira, C.A. Alonso, G.D. Paveto, M.C. Flawiá, M.M. Torres, H.N. L-arginine uptake and L-phosphoarginine synthesis in Trypanosoma cruzi
topic_facet	Amino acid transport Arginine kinase Canavanine Epimastigotes Homoarginine Phosphagen amino acid synthesis amino acid transport arginine canavanine citrulline energy metabolism homoarginine microbe metabolism ornithine phosphoarginine Trypanosoma Trypanosoma cruzi Trypanosoma cruzi
description	A very specific L-arginine transporter showing high affinity has been characterized in Trypanosoma cruzi epimastigotes. Uptake was found to be dependent on L-arginine concentration and it was saturable. Values for maximum velocity and Km ranged between 48.1-57.5 pmol·min-1 per 3 x 107 cells and between 4.2-5.5 μM, respectively The calculated activation energy and Q10 were 31.1 KJ·mol-1, and 1.7, respectively. Uptake velocity significantly increased when cells were preincubated in the absence of L-arginine. Cells retained the labeled amino acid independently of the presence or absence of exogenous L-arginine. The specificity of L-arginine uptake was demonstrated by competition assays in the presence of 80-fold molar excess of natural amino acids and several L-arginine derivatives. The highest levels of inhibition were caused by L-homoarginine. D-arginine, L-canavanine, L-ornithine, and L-citrulline, L-arginine uptake by T. cruzi epimastigotes was not affected by the presence of potassium or sodium ions in the incubation mixture or by pH changes in the range between 5.5-8.5. The major product of L-arginine uptake was characterized as phosphoarginine. Moreover, arginine kinase activity was detected in soluble extracts from T. cruzi epimastigotes.
format	JOUR
author	Pereira, C.A. Alonso, G.D. Paveto, M.C. Flawiá, M.M. Torres, H.N.
author_facet	Pereira, C.A. Alonso, G.D. Paveto, M.C. Flawiá, M.M. Torres, H.N.
author_sort	Pereira, C.A.
title	L-arginine uptake and L-phosphoarginine synthesis in Trypanosoma cruzi
title_short	L-arginine uptake and L-phosphoarginine synthesis in Trypanosoma cruzi
title_full	L-arginine uptake and L-phosphoarginine synthesis in Trypanosoma cruzi
title_fullStr	L-arginine uptake and L-phosphoarginine synthesis in Trypanosoma cruzi
title_full_unstemmed	L-arginine uptake and L-phosphoarginine synthesis in Trypanosoma cruzi
title_sort	l-arginine uptake and l-phosphoarginine synthesis in trypanosoma cruzi
url	http://hdl.handle.net/20.500.12110/paper_10665234_v46_n6_p566_Pereira
work_keys_str_mv	AT pereiraca larginineuptakeandlphosphoargininesynthesisintrypanosomacruzi AT alonsogd larginineuptakeandlphosphoargininesynthesisintrypanosomacruzi AT pavetomc larginineuptakeandlphosphoargininesynthesisintrypanosomacruzi AT flawiamm larginineuptakeandlphosphoargininesynthesisintrypanosomacruzi AT torreshn larginineuptakeandlphosphoargininesynthesisintrypanosomacruzi
_version_	1782025227761352704

L-arginine uptake and L-phosphoarginine synthesis in Trypanosoma cruzi

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