[Detection and characteristics of rpoB gene mutations in rifampicin-resistant clinical strains of M. tuberculosis].
The resistance of M. tuberculosis to rifampicin, one of the key agents used in the treatment of tuberculosis is due to point mutations in the rpoB gene encoding for the B-subunit of PNA polymerase. Based on the detection of such mutations, genotypic determinations of rifampicin resistance is a serous alternative to routine microbiological assays that take much more time. Nevertheless, the efficiency of genotypic methods largely depends how completely the resistance-associated mutations are studied and characterized. It is shown that the types and detection rates of certain rpoB mutations can greatly vary in the Mycobacterium strains spread in different geographical regions. By applying the approach based on the direct sequencing of PCR with rpoB gene fragments, the present paper analyzed 48 rifampicin-sensitive and 52 rifampicin-resistant clinical M. tuberculosis strains provided by Moscow tuberculous control facilities. Mutations responsible for rifampicin resistance were detected in 51 (98%) of the 52 resistant strains. The mutations involving codons 531 (46%), 526 (23%), and 516 (23%) of the rpoB gene were proved to be dominant. An unusual double mutation combining the replacement of F by L in codon 514 and previously uncharacterized methionine deletion in the position 515 was detected in the single investigated strain. The efficiency of the employed approach for rapid diagnosis of rifampicin-resistant M. tuberculosis strains is discussed.
Generozov
E V
EV
Al'tshuler
M L
ML
Govorun
V M
VM
Lopukhin
Iu M
IuM
Golyshevskaia
V I
VI
Chernousova
L N
LN
Khomenko
A G
AG
D000904:Antibiotics, Antitubercular / Q000494:pharmacology*; D003062:Codon / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004352:Drug Resistance, Microbial / Q000235:genetics*; D005838:Genotype; D006801:Humans; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D012293:Rifampin / Q000494:pharmacology*
D000904:Antibiotics, Antitubercular; D003062:Codon; D004269:DNA, Bacterial; D012293:Rifampin
Detektsiia i kharakteristika mutatsiĭ v gene rpoB rezistentnykh k rifampitsinu klinicheskikh shtammov M. tuberculosis.