Heat shock promoter of thermophilic chaperonin operon

The translation of a heat shock protein (HSP), TGroEL, of thermophilic bacterium PS3 increased within 10 minutes when the culture temperature was raised from 60 degrees C to 70 degrees C. In contrast to hyperthermophilic HSPs such as Pyrodictium ATPase, TGroEL is homologous to GroEL of E. coli (Tamada et al. (1991) Biochem. Biophys. Res. Commun. 197, 565-571). The promoter of the thermophilic heat shock gene (tgrE) was sequenced to analyze the heat shock response. The sequences of the promoter were CCTACTTGCA (-35 region) and GTTCATTAATA (-10 region), which are more heat labile than those of the sigma 32 recognition sites of GroEL. The expression of this homologous tgrE in E. coli may be lethal to the cells. The ATPase alpha subunit of this thermophile is also homologous to TGroEL.