Stabilization by fusion to the C-terminus of hyperthermophile Sulfolobus tokodaii RNase HI: a possibility of protein stabilization tag.

Kazufumi Takano
Tomohiro Okamoto
Jun Okada
Shun-ichi Tanaka
Clement Angkawidjaja
Yuichi Koga
Shigenori Kanaya

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.

PloS one

6

1

e16226

10.1371/journal.pone.0016226

https://doi.org/10.1371/journal.pone.0016226
https://www.ncbi.nlm.nih.gov/pubmed/21283826
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3023800
http://www.scopus.com/inward/record.url?eid=2-s2.0-79251638276&partnerID=MN8TOARS
http://orcid.org/0000-0002-7548-7314