Linked Life Data

20150242

Source:http://linkedlifedata.com/resource/pubmed/id/20150242

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 5
pubmed:dateCreated
2010-5-3
pubmed:abstractText
The startling increase in the occurrence of rifampicin (Rif) resistance in the clinical isolates of Mycobacterium tuberculosis worldwide is posing a serious concern to tuberculosis management. The majority of Rif resistance in bacteria arises from mutations in the RpoB subunit of the RNA polymerase. We isolated M. smegmatis strains harbouring either an insertion (6 aa) or a deletion (10 aa) in their RpoB proteins. Although these strains showed a compromised fitness for growth in 7H9 Middlebrook medium, their resistance to Rif was remarkably high. The attenuated growth of the strains correlated with decreased specific activities of the RNA polymerases from the mutants. While the RNA polymerases from the parent or a mutant strain (harbouring a frequently occurring mutation, H442Y, in RpoB) were susceptible to Rif-mediated inhibition of transcription from calf thymus DNA, those from the insertion and deletion mutants were essentially refractory to such inhibition. Three-dimensional structure modelling revealed that the RpoB amino acids that interact with Rif are either deleted or unable to interact with Rif due to their unsuitable spatial positioning in these mutants. We discuss possible uses of the RpoB mutants in studying transcriptional regulation in mycobacteria and as potential targets for drug design.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1465-2080
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
156
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1565-73
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Novel insertion and deletion mutants of RpoB that render Mycobacterium smegmatis RNA polymerase resistant to rifampicin-mediated inhibition of transcription.
pubmed:affiliation
Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't