Characterization of low molecular weight protein tyrosine phosphatases of Entamoeba histolytica.

Autor: Sierra-López F; Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del I.P.N., Ciudad de México, Mexico. Electronic address: fsierra@cinvestav.mx., Baylón-Pacheco L; Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del I.P.N., Ciudad de México, Mexico. Electronic address: lbaylon@cinvestav.mx., Vanegas-Villa SC; Programa de Doctorado en Ciencias Biomédicas, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de, Mexico. Electronic address: cyndy_17@hotmail.com., Rosales-Encina JL; Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del I.P.N., Ciudad de México, Mexico. Electronic address: rosales@cinvestav.mx.
Jazyk: angličtina
Zdroj: Biochimie [Biochimie] 2021 Jan; Vol. 180, pp. 43-53. Date of Electronic Publication: 2020 Oct 26.
DOI: 10.1016/j.biochi.2020.10.015
Abstrakt: Entamoeba histolytica is an intestinal protozoan parasite of humans and is endemic in developing countries. E. histolytica has two low molecular weight protein tyrosine phosphatase (LMW-PTP) genes, EhLMW-PTP1 and EhLMW-PTP2, which are expressed in cultured trophozoites, clinical isolates, and cysts. The amino acid sequences of proteins EhLMW-PTP1 and EhLMW-PTP2 showed only one amino acid difference between them at position A85V, respectively. Both genes are expressed in cultured trophozoites, mainly EhLMW-PTP2, and in trophozoites recovered from amoebic liver abscess, the expression of EhLMW-PTP1 is downregulated. We cloned the two genes and purified the corresponding recombinant (rEhLMW-PTPs) proteins. Antibodies anti-rEhLMW-PTP2 showed that during red blood cells uptake by E. histolytica, the EhLMW-PTPs were found in the phagocytic cups based on analysis of fluorescence signals. On the other hand, rEhLMW-PTPs showed an optimum phosphatase activity at pH 6.0 with p-nitrophenyl phosphate as the substrate. They dephosphorylate phosphotyrosine and 3-O-methylfluorescein phosphate, but not phosphoserine or phosphothreonine, and the enzymatic activity is inhibited by orthovanadate. rEhLMW-PTP1 and rEhLMW-PTP2 exhibited optimum temperatures of activities at 60 °C and 58 °C, respectively, with high thermal stability at 50 °C. Also, the rEhLMW-PTPs showed high specific activities and specific km value with pNPP or OMFP as the substrates at the physiological temperature (37 °C).
Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interests.
(Copyright © 2020 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.)
Databáze: MEDLINE
Externí odkaz: