Adaptation of Rhodococcus erythropolis cells for growth and bioremediation under extreme conditions.

02/01/2012

The bioremediation of contaminated sites is hardly performed in nature under ideal growth conditions for bacteria. Extremophiles can grow at extreme values of e.g. temperature, pH, ionic strength and metal concentrations but it may be difficult to find and isolate those with the required metabolic activities. In the present work, Rhodococcus erythropolis, a bacterium known to possess a large number of catabolic activities, was adapted to grow at 4-37ºC, pH 3-11 and in the presence of up to 7.5% sodium chloride and 1% copper sulphate. The large majority of the adapted cells were able to maintain the polarization of the membrane under the most difficult conditions tested and to adjust the net surface charge. The cells changed the composition of the fatty acids of the cellular membrane accordingly to the conditions endured. Changes in the relative proportion of straight, methyl and cyclopropyl saturated, unsaturated and hydroxyl substituted fatty acids were observed, as well as the production of polyunsaturated fatty acids unusual in bacteria. The adapted R. erythropolis cells were able to degrade C6-C16 n-alkanes and alcohols under the previously considered extreme conditions for this bacterium.

Authors in the community:

• 

  C

  Carla da Conceição Caramujo Rocha de Carvalho

  ist30853

  Affiliations and sources

  IST > iBB

  Instituto de Bioengenharia e Biociências

  IST > DBE

  Departamento de Bioengenharia

  In: scopus

  ID: 2-s2.0-84858009185

  In: orcid

  ID: 21860277

Research in Microbiology

125

136

163

2

10.1016/j.resmic.2011.11.003

industrial-biotechnology - Industrial Biotechnology

eng - English