Gene cloning and characterization of recombinant RNase HII from a hyperthermophilic archaeon.

ABSTRACT: We have cloned the gene encoding RNase HII (RNase HIIPk) from the hyperthermophilic archaeon Pyrococcus kodakaraensis KOD1 by screening of a library for clones that suppressed the temperature-sensitive growth phenotype of an rnh mutant strain of Escherichia coli. This gene was expressed in an rnh mutant strain of E. coli, the recombinant enzyme was purified, and its biochemical properties were compared with those of E. coli RNases HI and HII. RNase HIIPk is composed of 228 amino acid residues (molecular weight, 25,799) and acts as a monomer. Its amino acid sequence showed little similarity to those of enzymes that are members of the RNase HI family of proteins but showed 40, 31, and 25% identities to those of Methanococcus jannaschii, Saccharomyces cerevisiae, and E. coli RNase HII protein

SUBMITTER: Haruki M 

PROVIDER: S-EPMC107705 | biostudies-literature | 1998 Dec

REPOSITORIES: biostudies-literature