title: Stabilization by fusion to the C-terminus of hyperthermophile Sulfolobus tokodaii RNase HI: a possibility of protein stabilization tag.
abstract: RNase HI from the hyperthermophile Sulfolobus tokodaii (Sto-RNase HI) is stabilized by its C-terminal residues. In this work, the stabilization effect of the Sto-RNase HI C-terminal residues was investigated in detail by thermodynamic measurements of the stability of variants lacking the disulfide bond (C58/145A), or the six C-terminal residues (ΔC6) and by structural analysis of ΔC6. The results showed that the C-terminal does not affect overall structure and stabilization is caused by local interactions of the C-terminal, suggesting that the C-terminal residues could be used as a "stabilization tag." The Sto-RNase HI C-terminal residues (-IGCIILT) were introduced as a tag on three proteins. Each chimeric protein was more stable than its wild-type protein. These results suggested the possibility of a simple stabilization technique using a stabilization tag such as Sto-RNase HI C-terminal residues.
authors.affiliation: Department of Material and Life Science, Osaka University, Osaka, Japan. ktakano@mls.eng.osaka-u.ac.jp
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Takano
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Okamoto
authors.forename: Jun
authors.initials: J
authors.lastname: Okada
authors.forename: Shun-ichi
authors.initials: S
authors.lastname: Tanaka
authors.forename: Clement
authors.initials: C
authors.lastname: Angkawidjaja
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Koga
authors.forename: Shigenori
authors.initials: S
authors.lastname: Kanaya
mesh_terms: D000595:Amino Acid Sequence; D014644:Genetic Variation; D008722:Methods; D055550:Protein Stability; D011993:Recombinant Fusion Proteins / Q000737:chemistry*; D016914:Ribonuclease H / Q000737:chemistry* / Q000235:genetics; D016944:Sulfolobus / Q000201:enzymology*; D013816:Thermodynamics
chemical_list: D011993:Recombinant Fusion Proteins; D016914:Ribonuclease H; C078856:ribonuclease HI