Open AccessA Riboswitch Regulates Expression of the Coenzyme B 12 -Independent Methionine Synthase in Mycobacterium tuberculosis : Implications for Differential Methionine Synthase Function in Strains H37Rv and CDC1551
Author(s) -
Digby F. Warner,
Suzana Savvi,
Valerie Mizrahi,
Stephanie S. Dawes
Publication year - 2007
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.00040-07
Subject(s) - methionine synthase , biology , riboswitch , methionine , atp synthase , mycobacterium tuberculosis , microbiology and biotechnology , mutant , coenzyme a , biochemistry , gene , gene expression , enzyme , tuberculosis , amino acid , non coding rna , medicine , pathology , reductase
We observed vitamin B12 -mediated growth inhibition ofMycobacterium tuberculosis strain CDC1551. The B12 sensitivity was mapped to a polymorphism inmetH , encoding a coenzyme B12 -dependent methionine synthase. Vitamin B12 -resistant suppressor mutants of CDC1551 containing mutations in a B12 riboswitch upstream of themetE gene, which encodes a B12 -independent methionine synthase, were isolated. Expression analysis confirmed that the B12 riboswitch is a transcriptional regulator ofmetE inM. tuberculosis .