Article

Biological cost and compensatory evolution in fusidic acid-resistant Staphylococcus aureus.

Department of Cell and Molecular Biology, Box 596, Biomedical Center, S-751 24 Uppsala, Sweden.
Molecular Microbiology (impact factor: 5.01). 05/2001; 40(2):433-9. pp.433-9
Source: PubMed

ABSTRACT Fusidic acid resistance resulting from mutations in elongation factor G (EF-G) of Staphylococcus aureus is associated with fitness costs during growth in vivo and in vitro. In both environments, these costs can be partly or fully compensated by the acquisition of secondary intragenic mutations. Among clinical isolates of S. aureus, fusidic acid-resistant strains have been identified that carry multiple mutations in EF-G at positions similar to those shown experimentally to cause resistance and fitness compensation. This observation suggests that fitness-compensatory mutations may be an important aspect of the evolution of antibiotic resistance in the clinical environment, and may contribute to a stabilization of the resistant bacteria present in a bacterial population.

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    Article: Structure and function of FusB: an elongation factor G-binding fusidic acid resistance protein active in ribosomal translocation and recycling.
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    Open biology. 03/2012; 2(3):120016.

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Keywords

carry multiple mutations
 
costs
 
elongation factor G
 
fitness compensation
 
fitness costs
 
fitness-compensatory mutations
 
Fusidic acid resistance
 
fusidic acid-resistant strains
 
mutations
 
resistant bacteria present
 
S. aureus
 
secondary intragenic mutations
 
Staphylococcus aureus
 
vivo