 |
PDBsum entry 1io2
|
|
|
|
|
 |
Contents |
 |
|
|
|
|
|
|
|
|
|
|
* Residue conservation analysis
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
Catalytic center of an archaeal type 2 ribonuclease h as revealed by X-Ray crystallographic and mutational analyses.
|
|
|
Authors
|
|
A.Muroya,
D.Tsuchiya,
M.Ishikawa,
M.Haruki,
M.Morikawa,
S.Kanaya,
K.Morikawa.
|
|
|
Ref.
|
|
Protein Sci, 2001,
10,
707-714.
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
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.
|
|
|
|
|
|
|
