Premium
Characterization of RNA polymerse and two sigma‐factor genes from Mycobacterium smegmatis
Author(s) -
Predich Mima,
Doukhan Laurence,
Nair Gopalan,
Smith Issar
Publication year - 1995
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1111/j.1365-2958.1995.tb02249.x
Subject(s) - mycobacterium smegmatis , sigma factor , rna polymerase , biology , transcription (linguistics) , gene , polymerase , bacillus subtilis , microbiology and biotechnology , transcription factor ii d , rna polymerase ii , rna polymerase i , rna polymerase ii holoenzyme , rna , rna dependent rna polymerase , specificity factor , promoter , genetics , gene expression , bacteria , mycobacterium tuberculosis , medicine , tuberculosis , linguistics , philosophy , pathology
Summary A search for Mycobacterium smegmatis genes showing similarity to the conserved family encoding major Sigma factors in diverse prokaryotes has identified two such determinants. Both genes are expressed in exponentially growing cells, as judged by Western immunoassays. A series of chromatographic steps was used to purify M. smegmatis RNA polymerase holoenzyme and it was shown that its ability to initiate in vitro transcription with a heterologous Bacillus subtilis promoter is dependent on the presence of these Sigma factor(s). Reconstitution of specific in vitro transcription activity was obtained upon mixing of M. smegmatis core RNA polymerase with the major Sigma factor of Bacillus subtilis. We also demonstrated in vitro transcription of the M. smegmatis rrnB promoter by the M. smegmatis RNA polymerase. Significantly, highly active B. subtilis RNA polymerase holoenzyme was unable to transcribe this gene.