Synthesis of Heat Shock Proteins in Thermoanaerobacterium

The response to heat stress was examined in Thermoanaerobacterium thermosulfurigenes EM1. Upon a temperature shift-up from 50 ~ to 62~ four heat shock proteins (hsps) were synthesized at an elevated level. Two proteins were found to be immunologically related to the Escherichia c oli GroEL protein and the Mycobacterium tuberculosis hsp71 (DnaK similar protein), and the correspondinggroE and dnaK homologous sequences were detected in the chromosome of T. thermosuO~rigenes EM1. The heat shock response in this thermophile was transient, with a maximum synthesis of hsps between 10 and 15 min after the shock. The enhanced synthesis of DnaK and GroEL was consistent with increased mRNA levels of the genes, which reached a maximum 15 rain after heat treatment. The biology of thermophilic eubacteria and archaea has been extensively studied in recent years. The function of these microorganisms in nature and their potential use in biotechnology, e.g., for producing