GENE OF HEAT-SHOCK PROTEIN OF SULFUR-DEPENDENT ARCHAEAL HYPERTHERMOPHILE DESULFUROCOCCUS

To elucidate thermoresistance, a gene of a hyperthermophilic heat shoc k protein (HHSP) was isolated from the hyperthermophile Desulfurococcu s strain SY which grows at 95 degrees C. The molecular weight of HHSP deduced from the open reading frame was 59,137 (545 amino acid residue s). Sequence alignments of peptides reveal similarities (evolutionary distances) to the alpha (0.279) and beta (0.296) subunits of thermosom e, TF55 (0.343) and human t-complex polypeptide 1. The structure of a thermophilic heat shock protein TGroEL (Tamada et al. (1991) Biochem. Biophys. Res. Commun. 179, 565) was quite different from that of HHSP. TGroEL and HSP60 have sequences identical to HHSP at its equatorial d omain, while those identical to the alpha subunit of F-type ATPase are at its apical domain. (C) 1995 Academic Press, Inc.