Effect of ibpAB availability on the proteome composition after two hours of α-glucosidase production at 42°C. After growth at 37°C to OD600 of 0.5, cultures were induced with 1 mM IPTG, and transferred to 42°C. Two hours later, cells were harvested and the proteome was separated by two-dimensional gel-electrophoresis. Silver-stained two-dimensional gels of (A) wildtype strain with or (B) without ibpAB overexpression, and of (C) the ibp AB deletion strain. Reference spots used for normalisation of spot intensities after densitometry are indicated by circles. Positions of selected proteins (cf. text) are indicated.