| RRC ID |
5311
|
| 著者 |
Nakayama H, Shimamura T, Imagawa T, Shirai N, Itoh T, Sako Y, Miyano M, Sakuraba H, Ohshima T, Nomura N, Tsuge H.
|
| タイトル |
Structure of a hyperthermophilic archaeal homing endonuclease, I-Tsp061I: contribution of cross-domain polar networks to thermostability.
|
| ジャーナル |
J Mol Biol
|
| Abstract |
A novel LAGLIDADG-type homing endonuclease (HEase), I-Tsp061I, from the hyperthermophilic archaeon Thermoproteus sp. IC-061 16 S rRNA gene (rDNA) intron was characterized with respect to its structure, catalytic properties and thermostability. It was found that I-Tsp061I is a HEase isoschizomer of the previously described I-PogI and exhibits the highest thermostability among the known LAGLIDADG-type HEases. Determination of the crystal structure of I-Tsp061I at 2.1 A resolution using the multiple isomorphous replacement and anomalous scattering method revealed that the overall fold is similar to that of other known LAGLIDADG-type HEases, despite little sequence similarity between I-Tsp061I and those HEases. However, I-Tsp061I contains important cross-domain polar networks, unlike its mesophilic counterparts. Notably, the polar network Tyr6-Asp104-His180-107O-HOH12-104O-Asn177 exists across the two packed alpha-helices containing both the LAGLIDADG catalytic motif and the GxxxG hydrophobic helix bundle motif. Another important structural feature is the salt-bridge network Asp29-Arg31-Glu182 across N and C-terminal domain interface, which appears to contribute to the stability of the domain/domain packing. On the basis of these structural analyses and extensive mutational studies, we conclude that such cross-domain polar networks play key roles in stabilizing the catalytic center and domain packing, and underlie the hyperthermostability of I-Tsp061I.
|
| 巻・号 |
365(2)
|
| ページ |
362-78
|
| 公開日 |
2007-1-12
|
| DOI |
10.1016/j.jmb.2006.09.066
|
| PII |
S0022-2836(06)01290-3
|
| PMID |
17069851
|
| MeSH |
Amino Acid Motifs
Amino Acid Sequence
Archaeal Proteins / chemistry*
Archaeal Proteins / genetics
Binding Sites
Crystallization
Crystallography, X-Ray
Endonucleases / chemistry*
Endonucleases / genetics
Enzyme Stability
Molecular Sequence Data
Protein Structure, Tertiary
Sequence Homology, Amino Acid
Structure-Activity Relationship
Thermoproteus / enzymology*
|
| IF |
4.76
|
| 引用数 |
9
|
|
WOS 分野
|
BIOCHEMISTRY & MOLECULAR BIOLOGY
|
| リソース情報 |
| 一般微生物 |
JCM10595 |
