Discontinuous occurrence of the hsp70 (dnaK) gene among Archaea and sequence features of HSP70 suggest a novel outlook on phylogenies inferred from this protein.

ABSTRACT: Occurrence of the hsp70 (dnaK) gene was investigated in various members of the domain Archaea comprising both euryarchaeotes and crenarchaeotes and in the hyperthermophilic bacteria Aquifex pyrophilus and Thermotoga maritima representing the deepest offshoots in phylogenetic trees of bacterial 16S rRNA sequences. The gene was not detected in 8 of 10 archaea examined but was found in A. pyrophilus and T. maritima, from which it was cloned and sequenced. Comparative analyses of the HSP70 amino acid sequences encoded in these genes, and others in the databases, showed that (i) in accordance with the vicinities seen in rRNA-based trees, the proteins from A. pyrophilus and T. maritima form a thermophilic cluster with that from the green nonsulfur bacterium Thermomicrobium roseum and are unrelat

SUBMITTER: Gribaldo S 

PROVIDER: S-EPMC93396 | biostudies-literature | 1999 Jan

REPOSITORIES: biostudies-literature