FIG. 5.

Northern blot analysis of Lactobacillus groESL mRNA isolated from cultures maintained under normal or heat shock conditions. Total RNA was isolated from log phase cultures maintained at 37 or 55°C, and 10-μg volumes were separated by electrophoresis through multiple 1.5% agarose–formaldehyde gels and transferred to nylon membranes. Lane 0 contains RNA isolated prior to the temperature shift, lanes 10 to 60 contain RNA isolated at 10-min intervals after the temperature shift, and lane M contains RNA molecular weight markers (Gibco/BRL). (A) Representative agarose-formaldehyde gel which has been stained with ethidium bromide and photographed. (B and C) Northern blots were probed with either a 107-bp fragment specific for the groESL promoter region (B) or a 153-bp fragment specific for groES (C).