このエントリーをはてなブックマークに追加
ID 48607
file
creator
Hasegawa, Jun
Shimahara, Hideto
Mizutani, Masayuki
Uchiyama, Susumu
Arai, Hiroyuki
Ishii, Masaharu
Kobayashi, Yuji
Ferguson, Stuart J.
Igarashi, Yasuo
abstract
A heterologous overexpression system for mesophilic Pseudomonas aeruginosa holocytochrome c551 (PA c551) was established using Escherichia coli as a host organism. Amino acid residues were systematically substituted in three regions of PA c551 with the corresponding residues from thermophilic Hydrogenobacter thermophilus cytochrome c552 (HT c552), which has similar main chain folding to PA c551, but is more stable to heat. Thermodynamic properties of PA c551 with one of three single mutations (Phe-7 to Ala, Phe-34 to Tyr, or Val-78 to Ile) showed that these mutants had increased thermostability compared with that of the wild-type. Ala-7 and Ile-78 may contribute to the thermostability by tighter hydrophobic packing, which is indicated by the three dimensional structure comparison of PA c551 with HT c552. In the Phe-34 to Tyr mutant, the hydroxyl group of the Tyr residue and the guanidyl base of Arg-47 formed a hydrogen bond, which did not exist between the corresponding residues in HT c552. We also found that stability of mutant proteins to denaturation by guanidine hydrochloride correlated with that against the thermal denaturation. These results and others described here suggest that significant stabilization of PA c551 can be achieved through a few amino acid substitutions determined by molecular modeling with reference to the structure of HT c552. The higher stability of HT c552 may in part be attributed to some of these substitutions.
description
This work was supported in part by grants from the Japanese Ministry of Education, Science and Culture.
journal title
Journal of Biological Chemistry
volume
Volume 274
issue
Issue 53
start page
37533
end page
37537
date of issued
1999-12-31
publisher
The American Society for Biochemistry and Molecular Biology, Inc.
issn
0021-9258
1083-351X
publisher doi
pubmed id
language
eng
nii type
Journal Article
HU type
Journal Articles
DCMI type
text
format
application/pdf
text version
publisher
rights
This research was originally published in the Journal of Biological Chemistry. Jun Hasegawa, Hideto Shimahara, Masayuki Mizutani, Susumu Uchiyama, Hiroyuki Arai, Masaharu Ishii, Yuji Kobayashi, Stuart J. Ferguson, Yoshihiro Sambongi and Yasuo Igarashi. Stabilization of Pseudomonas aeruginosa Cytochrome c551 by Systematic Amino Acid Substitutions Based on the Structure of Thermophilic Hydrogenobacter thermophilus Cytochrome c552. J. Biol. Chem. 1999; 274(53):37533-37537. © the American Society for Biochemistry and Molecular Biology.
relation url
department
Graduate School of Integrated Sciences for Life