rpoB

The rpoB gene encodes the β subunit of bacterial RNA polymerase. It is the site of mutations that confer resistance to the rifamycin antibacterial agents, such as rifampin.[1] Mutations in rpoB that confer resistance to rifamycins do so by altering residues of the rifamycin binding site on RNA polymerase, thereby reducing rifamycin binding affinity for rifamycins[2][3]

Nucleic acid probes can detect mutations in rpoB that confer rifampicin resistance. For Mycobacterium tuberculosis, the rifamycin-resistant mutations most commonly encountered involve codons 516, 526, and 531 (numbered, by convention, as in Escherichia coli rpoB).[4][5] For Staphylococcus aureus, the rifamycin-resistant mutation most commonly encountered involves codon 526.[6]

References

  1. Floss, H.G.; Yu, T. (2005). "Rifamycin-Mode of Action, Resistance, and Biosynthesis". Chem. Rev. 105 (2): 621–32. doi:10.1021/cr030112j. PMID 15700959.
  2. Campbell, E.A., Korzheva, N., Mustaev, A., Murakami, K., Nair, S., Goldfarb, A., Darst, S.A. (2001). "Structural mechanism for rifampicin inhibition of bacterial RNA polymerase". Cell 104 (6): 901–12. doi:10.1016/S0092-8674(01)00286-0. PMID 11290327.
  3. Feklistov, A., Mekler, V., Jiang, Q., Westblade, L.F., Irschik, H., Jansen, R., Mustaev, A., Darst, S.A., Ebright, R.H. (2008). "Rifamycins do not function by allosteric modulation of binding of Mg2+ to the RNA polymerase active center". Proc Natl Acad Sci USA 105 (39): 14820–5. doi:10.1073/pnas.0802822105. PMC 2567451. PMID 18787125.
  4. Mokrousov, I.; Otten, T.; Vyshnevskiy, B.; Narvskaya, O. (2003). "Allele-Specific rpoB PCR Assays for Detection of Rifampin-Resistant Mycobacterium tuberculosis in Sputum Smears". Antimicrob Agents Chemother 47 (7): 22312235. doi:10.1128/AAC.47.7.2231-2235.2003. PMC 161874. PMID 12821473.
  5. Telenti A, Imboden P, Marchesi F et al. (1993). "Detection of rifampicin-resistance mutations in Mycobacterium tuberculosis". Lancet 341 (8846): 64750. doi:10.1016/0140-6736(93)90417-F. PMID 8095569.
  6. Wichelhaus TA, Schäfer V, Brade V, Böddinghaus B (1999). "Molecular characterization of rpoB mutations conferring cross-resistance to rifamycins on methicillin-resistant Staphylococcus aureus". Antimicrob Agents Chemother 43 (11): 28132816. PMC 89569. PMID 10543773.