Biochemical and inhibition studies of glutamine synthetase from Leishmania donovani.
Microb Pathog
; 107: 164-174, 2017 Jun.
Article
em En
| MEDLINE
| ID: mdl-28351708
ABSTRACT
Leishmaniasis is a group of tropical diseases caused by protozoan parasites of the genus Leishmania. Leishmania donovani is a protozoan parasite that causes visceral leishmaniasis, a fatal disease if left untreated. Chemotherapy for leishmaniasis is problematic as the available drugs are toxic, costly and shows drug resistance, hence, there is a necessity to look out for the novel drug targets, chemical entities and vaccine. Glutamine synthetase (GS) catalyzes the synthesis of glutamine from glutamate and ammonia. In the present study, we have identified and characterized GS from L. donovani. The nucleotide sequence encoding putative glutamine synthetase like sequence from L. donovani (LdGS, LDBPK_060370) was cloned. A 43.5 kDa protein with 6X-His tag at the C-terminal end was obtained by overexpression of LdGS in Escherichia coli BL21 (DE3) strain. Expression of native LdGS in promastigotes and recombinant L. donovani glutamine synthetase (rLdGS) was confirmed by western blot analysis. An increase in expression of GS was observed at different phases of growth of the parasite. Expression of LdGS in promastigote and amastigote was confirmed by western blot analysis. Immunofluorescence studies of both the promastigote and amastigote stages of the parasite revealed the presence of LdGS in cytoplasm. GS exists as a single copy gene in parasite genome. Kinetic analysis of GS enzyme revealed Km value of 26.3 ± 0.4 mM for l- glutamate and Vmax value of 2.15 ± 0.07 U mg-1. Present study confirms the presence of glutamine synthetase in L. donovani and provides comprehensive overview of LdGS for further validating it as a potential drug target.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Leishmania donovani
/
Proteínas Recombinantes
/
Proteínas de Protozoários
/
Inibidores Enzimáticos
/
Glutamato-Amônia Ligase
Idioma:
En
Revista:
Microb Pathog
Assunto da revista:
DOENCAS TRANSMISSIVEIS
/
MICROBIOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Índia