Sept 26, 2007 an article has been published on line for publication in Applied Microbiology & Biotechnology prior to the printed publication Click here.

Abstract Appl Microbiol Biotechnol. 2007 Nov ;77(2):489-96. Epub 2007 Sep 26.

Development of a novel continuous culture device for experimental evolution of bacterial populations.

de Crécy E, Metzgar D, Allen C, Pénicaud M, Lyons B, Hansen CJ, de Crécy-Lagard V

Evolugate 5745 SW 75th St #188, Gainesville, FL 32608, USA

The availability of a robust and reliable continuous culture apparatus that eliminates wall growth problems would lead to many applications in the microbial field, including allowing genetically engineered strains to recover high fitness, improving biodegradation strains, and predicting likely antibiotic resistance mechanisms. We describe the design and implementation of a novel automated continuous culture machine that can be used both in time-dependent mode (similar to a chemostat) and turbidostat modes, in which wall growth is circumvented through the use of a long, variably divisible tube of growth medium. This tube can be restricted with clamps to create a mobile growth chamber region in which static portions of the tube and the associated medium are replaced together at equal rates. To functionally test the device as a tool for re-adaptation of engineered strains, we evolved a strain carrying a highly deleterious deletion of Elongation Factor P, a gene involved in translation. In 200 generations over 2 weeks of dilution cycles, the evolved strain improved in generation time by a factor of three, with no contaminations and easy manipulation.