Abstract
Mutations of the rpoB gene conferring resistance to rifampin were analyzed in 40 methicillin-resistant Staphylococcus aureus isolates obtained from six countries. Interestingly, the majority of clinical isolates showed multiple mutations within rpoB. The amino acid substitution 481His-->Asn was the most prevalent one, capable of conferring low-level resistance on its own. Cross-resistance to rifampin, rifabutin, and rifapentine was demonstrated for all mutants identified. The level of resistance to rifamycins correlated with both the mutation position and type of amino acid substitution.
MeSH terms
-
Amino Acid Sequence
-
Anti-Bacterial Agents / pharmacology*
-
DNA, Bacterial / analysis
-
DNA, Bacterial / genetics
-
DNA-Directed RNA Polymerases
-
Drug Resistance, Microbial
-
Electrophoresis, Polyacrylamide Gel
-
Escherichia coli / drug effects
-
Escherichia coli / genetics
-
Genotype
-
Humans
-
Methicillin Resistance / genetics
-
Microbial Sensitivity Tests
-
Molecular Sequence Data
-
Multigene Family / genetics
-
Plant Proteins / genetics*
-
Rifamycins / pharmacology*
-
Staphylococcal Infections / microbiology
-
Staphylococcus aureus / drug effects
-
Staphylococcus aureus / genetics*
Substances
-
Anti-Bacterial Agents
-
DNA, Bacterial
-
Plant Proteins
-
Rifamycins
-
RpoB protein, Oryza sativa
-
DNA-Directed RNA Polymerases