CLONING AND SEQUENCING OF THE HRCA GENE OF BACILLUS-STEAROTHERMOPHILUS

We report on cloning and sequencing of a 2.0-kb PCR fragment of chromo somal DNA from thermophilic Bacillus stearothermophilus carrying the c omplete hrcA gene. In addition, this amplicon contains the 3' end of a n open reading frame exhibiting significant homology to the hemN gene of Bacillus subtilis (Bs) and other bacterial species. The hrcA gene c ould complement an Bs hrcA deletion mutant by repressing expression of class I heat shock (HS) genes. Furthermore, we could show that the Hr cA protein derived from the thermophilic microorganism responds to HS in a similar way as reported for the Bs HrcA protein. (C) 1997 Elsevie r Science B.V.