SOPs

An aerobic chemostat culture (above 70% of oxygen saturation) was set up at the specified dilution rate (fraction culture volume per hour; equal to growth rate in steady-state) with a working volume of 1 litre in a 1.5 litre fermenter (Applikon, The Netherlands) using the specified synthetic defined nutrient-limited medium according to the description of Baganz et al., (1997)

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Biomass samples (20ml) were taken via the sample port of the Applikon fermenters. The cells were pelleted by centrifugation for 5min at 5000rpm. The supernatant was removed and the RNA pellet resuspended in the residual medium to form a slurry. This was added in a dropwise manner directly into a 5ml Teflon flask (B. Braun Biotech, Germany) containing liquid nitrogen and a 7mm-diameter tungsten carbide ball.

Taken from ArrayExpress: http://www.ebi.ac.uk/microarray-as/ae/browse.html?keywords=E-MEXP-115 ...

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