Figure 3.

Optimization of fed-batch cultivations for production of TaCel5A and AfCel12A. Fed-batch cultivations for producing TaCel5A (A, C, E) and AfCel12A (B, D, F) were performed in glycerol at 30°C (A, B), in glucose at 30°C (C, D) and in glycerol at 25°C (E, F). Carbon sources were introduced as a stepped feed of 2470 g (3.9 l) of glycerol or glucose over 70 h, following a 24-h batch phase, with an initial volume of 5 l. Fermentation parameters were controlled at standard settings (see Methods). Culture supernatant samples were collected at various time points and analyzed by SDS-PAGE (15 μl sample size). Sample lanes are marked with the age of the culture in hours. Bands marked as 37 kDa represent TaCel5A. Bands marked as 24 kDa represent AfCel12A. The protein standard was Mark12 Unstained Standard (Invitrogen). Additional data for these fermentations are provided in Table  1.