Evaluation of Bacillus anthracis thymidine kinase as a potential target for the development of antibacterial nucleoside analogs.
Biol Chem
; 387(12): 1575-81, 2006 Dec.
Article
em En
| MEDLINE
| ID: mdl-17132103
ABSTRACT
Bacillus anthracis, which causes anthrax, has attracted attention because of its potential use as a biological weapon. The risk of multidrug resistance against B. anthracis increases the need for antibiotics with new molecular targets. Nucleoside analogs are well-known antiviral and anticancer prodrugs, and thymidine kinase catalyzes the rate-limiting step in the activation of pyrimidine nucleoside analogs used in chemotherapy. The thymidine kinase gene from B. anthracis Sterne strain (34F2) (Ba-TK) was cloned and expressed in E. coli, and the product was purified and characterized regarding its substrate specificity. Ba-TK phosphorylated pyrimidine nucleosides and all natural nucleoside triphosphates served as phosphate donors. Size exclusion chromatography indicated a dimeric form of Ba-TK, regardless of the presence of ATP. Thymidine was the most efficient substrate with a low K(m) value (0.6 microM) and a V(max) of 3.3 micromol dTMP mg(-1) min(-1), but deoxyuridine (K(m)=4.2 microM, V(max)=4.1 micromol dUMP mg(-1) min(-1)) was also a good substrate. Several pyrimidine analogs were also tested and analogs with 5-position modifications showed higher activities compared to analogs with 3'- and N3-position modifications. Deoxyuridine analogs were the most potent inhibitors of B. anthracis growth in vitro. These results may be used to guide future development of nucleoside analogs against B. anthracis.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Timidina Quinase
/
Bacillus subtilis
/
Antibacterianos
/
Nucleosídeos
Limite:
Humans
Idioma:
En
Ano de publicação:
2006
Tipo de documento:
Article