Characterization of an ecto-5′-nucleotidase (EC 3.1.3.5) activity in intact cells of Trichomonas vaginalis

被引：30

作者：

Tasca, T

Bonan, CD

De Carli, GA

Battastini, AMO

Sarkis, JJF

机构：

[1] Univ Fed Rio Grande Sul, Inst ciencias Basicas Saude, Dept Bioquim, BR-90035003 Porto Alegre, RS, Brazil

[2] Pontificia Univ Catolica Rio Grande Sul, Fac Farm, Dept Anal Clin, Lab Parasitol Clin, BR-90619900 Porto Alegre, RS, Brazil

[3] Pontificia Univ Catolica Rio Grande Sul, Fac Biocinecias, Dept Ciencias Fisiol, Lab Pesquisa Bioquim, BR-90619900 Porto Alegre, RS, Brazil

来源：

EXPERIMENTAL PARASITOLOGY | 2003年 / 105卷 / 02期

关键词：

Trichomonas vaginalisl; parasitic protozoan; intact cells; ecto-5 '-nucleotidase; adenosine; NTPDasel; nucleoside triphosphate diphosphohydrolase 1 (EC 3.6.1.5); NTPDase2; nucleoside triphosphate diphosphohydrolase 2 (EC 3.6.1.3); ecto-5 '-nucleotidase (EC 3.1.3.5); CMP; cytidine Y-monophosphate; 5 '-monophosphate; K-m; Michaelis constant; V-max; maximum velocity; 3; 5; '-cAMP; 5 '-cyclic monophosphate; NAD(+); nicotinamide adenine dinucleotide; Ap(n)A; diadenosine polyphosphates; AMPCP; alpha; beta-methylene adenosine diphosphate;

D O I：

10.1016/j.exppara.2003.12.001

中图分类号：

R38 [医学寄生虫学]; Q [生物科学];

学科分类号：

07 ; 0710 ; 09 ; 100103 ;

摘要：

The enzymatic properties of an ecto-5'-nucleotidase were described in Trichomonas vaginalis. The enzyme hydrolyzes nucleoside monophosphates in optimum pH values of 7.5 and 6.5 for the 30236 strain and for the 30238 strain, respectively. Mg2+ and Ca2+ were activators of AMP hydrolysis in both strains. The apparent K-m (Michaelis constant) values for Mg2+-AMP were 111.4 +/- 28.1 muM (mean +/- SD, n = 3) for 30236 strain and 420.2 +/- 35.7 muM (mean +/- SD, n = 3) for 30238 strain. The ecto-5'-nucleotidase activity was insensitive to levamisole and tetramisole, inhibitors of alkaline phosphatases, whereas alpha,beta-methylene-ADP inhibited the enzymatic activity of both strains. Our results showed that the AMP hydrolysis presents differences in some kinetic parameters between the two strains investigated. An analysis of the enzymatic chain involved in the ATP hydrolysis to adenosine will contribute to understanding the biochemical aspects of the parasite and the mechanisms related to host-parasite interactions. (C) 2003 Elsevier Inc. All rights reserved.

引用

页码：167 / 173

页数：7

共 42 条

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