1io2

Publication Abstract from PubMed

The catalytic center of an archaeal Type 2 RNase H has been identified by a combination of X-ray crystallographic and mutational analyses. The crystal structure of the Type 2 RNase H from Thermococcus kodakaraensis KOD1 has revealed that the N-terminal major domain adopts the RNase H fold, despite the poor sequence similarity to the Type 1 RNase H. Mutational analyses showed that the catalytic reaction requires four acidic residues, which are well conserved in the Type 1 RNase H and the members of the polynucleotidyl transferase family. Thus, the Type 1 and Type 2 RNases H seem to share a common catalytic mechanism, except for the requirement of histidine as a general base in the former enzyme. Combined with the results from deletion mutant analyses, the structure suggests that the C-terminal domain of the Type 2 RNase H is involved in the interaction with the DNA/RNA hybrid.

Catalytic center of an archaeal type 2 ribonuclease H as revealed by X-ray crystallographic and mutational analyses.,Muroya A, Tsuchiya D, Ishikawa M, Haruki M, Morikawa M, Kanaya S, Morikawa K Protein Sci. 2001 Apr;10(4):707-14. PMID:11274461^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.