Format

Send to

Choose Destination
Curr Biol. 2001 Nov 13;11(22):1810-4.

Phenotypic switching of antibiotic resistance circumvents permanent costs in Staphylococcus aureus.

Author information

1
Nuffield Department of Clinical Laboratory Sciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom. ruth.massey@ndcls.ox.ac.uk

Abstract

Bacterial antibiotic resistance is often associated with a fitness cost in the absence of the antibiotic [1,2]. We have examined a resistance mechanism in Staphylococcus aureus that negates these costs. Exposure to gentamicin both in vitro and in vivo has been reported to result in the emergence of a gentamicin-resistant small colony variant (SCV)[3-8]. We show that the emergence of SCVs following exposure to gentamicin results from a rapid switch and that bacteria exposed to cycles of gentamicin followed by antibiotic-free medium repeatedly switched between a resistant SCV and a sensitive parental phenotype (revertants). The fitness of revertants relative to S. aureus with stable gentamicin resistance was greater in drug-free media, which suggests that S. aureus has evolved an inducible and reversible resistance mechanism that circumvents a permanent cost to fitness.

PMID:
11719226
DOI:
10.1016/s0960-9822(01)00507-3
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center