Remarkable activity enhancement of thermolysin mutants

FEBS Letters

Miyake, Toshio²  Endo, Kimiko¹  Wada, Akiyoshi¹  Yoneya, Takashi²  Kidokoro, Shun-ichi¹  Miki, Yoichiro¹  Aoyama, Atsuo²  Nagao, Hiromasa²  Ooe, Seigo²  Kai, Kenichi² 

[1] Sagami Chemical Research Center, Nishiohnuma 4-4-1, Sagamihara, Kanagawa 229, Japan;TOSOH Corp. Biotechnology Research Laboratory, Hayakawa 2743-1, Ayase, Kanagawa 252, Japan

关键词: Enzyme stability;    Activity;    Design principle;    Amino acid mutation;    3D;    three-dimensional;    CD;    circular dichroism;    DSC;    differential scaning calorimetry;    FAGLA;    N-(3-[2-furyl]acryloyl)-glycyl-l-leucine amide;    FADFM;    methylester;   

DOI  :  10.1016/0014-5793(95)00537-J

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Most attempts to modify the properties of enzymes by amino acid substitution around the active sites have resulted in suppression of the biological activity, suggesting that the structure of natural enzymes should be almost optimized evolutionally to show the highest activity. In contrast, we found an interesting site of a well-known metalloendopeptidase, thermolysin (EC. 3.4.24.4), where almost all the amino acid replacement causes a remarkable increase in the hydrolytic activity. Negative correlation between the activity and the thermal stability was observed. The flexibility around the substrate binding site is suggested to be a key to the correlation. Nature may have selected the amino acid at this site, which suppresses the flexibility of the molecule, to get the highest thermal stability at the expense of the activity.

【 授权许可】

Unknown