Extremophiles

, Volume 7, Issue 5, pp 371–376

Comparative genomic analysis of solvent extrusion pumps in Pseudomonas strains exhibiting different degrees of solvent tolerance

  • Ana Segura
  • Antonia Rojas
  • Ana Hurtado
  • María-José Huertas
  • Juan L. Ramos
Original Paper

DOI: 10.1007/s00792-003-0331-x

Cite this article as:
Segura, A., Rojas, A., Hurtado, A. et al. Extremophiles (2003) 7: 371. doi:10.1007/s00792-003-0331-x

Abstract

Organic solvents are inherently toxic for microorganisms. Their effects depend not only on the nature of the compound, but also on the intrinsic tolerance of the bacterial species and strains. Three efflux pumps belonging to the RND (resistance-nodulation-cell division) family of multidrug extrusion pumps are the main factor involved in the high intrinsic tolerance to toluene of Pseudomonas putida DOT-T1E. We have analyzed the tolerance to toluene shocks [0.1% and 0.3% (v/v)] of a number of strains belonging to different species of the genus Pseudomonas upon growth in the absence and in the presence of sublethal concentrations of toluene. The strains can be grouped in three categories: (1) highly resistant strains, in which almost 100% of the cells precultured in the presence of sublethal concentrations of toluene withstood a 0.3% (v/v) toluene shock, (2) moderately resistant strains, in which only a fraction (10−4–1) of the cells withstood a 0.1% (v/v) toluene shock, but fewer than 1 in 107 cells survived a sudden 0.3% (v/v) toluene shock regardless of the growth conditions, and (3) sensitive strains, in which regardless of the growth conditions fewer than 10−5 cells survived a 0.1% (v/v) toluene shock. We also studied the number and type of efflux pumps in different strains in comparison with the P. putida DOT-T1E strain.

Keywords

Organic solventsPseudomonasRND efflux pumpsSolvent toleranceToluene resistanceToluene shocks

Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Ana Segura
    • 1
  • Antonia Rojas
    • 1
  • Ana Hurtado
    • 1
  • María-José Huertas
    • 2
  • Juan L. Ramos
    • 1
  1. 1.Consejo Superior de Investigaciones Cientificas, Departamento de Bioquímica y Biología Molecular y Celular de PlantasEstación Experimental del ZaidínGranadaSpain
  2. 2.Departamento de Bioquímica y Biología MolecularEdificio Severo Ochoa pta.1. Campus Universitario de RabanalesCórdobaSpain