کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1940741 1050787 2006 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
First functional characterization of a singly expressed bacterial type II topoisomerase: The enzyme from Mycobacterium tuberculosis
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
First functional characterization of a singly expressed bacterial type II topoisomerase: The enzyme from Mycobacterium tuberculosis
چکیده انگلیسی

Genome deciphering revealed that Mycobacterium tuberculosis encodes a single type II topoisomerase contrary to common bacteria harboring two type II topoisomerases (DNA gyrase and topoisomerase IV). Functions of the M. tuberculosis type II topoisomerase were explored after cloning and expressing the subunits encoding genes in Escherichia coli. M. tuberculosis type II topoisomerase supercoiled relaxed pBR322 with a specific activity close to that of DNA gyrases of common bacteria whereas it exhibited DNA relaxation and formation of cleavable complexes with activities significantly higher than other DNA gyrases. Intermolecular passage activity evaluated by the decatenation of kinetoplast DNA was 25-fold lower than that of the topoisomerase IV from Streptococcus pneumoniae, but was markedly higher than that of the E. coli gyrase. Overall, the type II topoisomerase of M. tuberculosis exhibits classical polyvalent activities of DNA gyrase for supercoiling but enhanced relaxation, cleavage, and decatenation activities.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochemical and Biophysical Research Communications - Volume 348, Issue 1, 15 September 2006, Pages 158–165
نویسندگان
, , , ,