Characterization of soluble artificial proteins with random sequences

FEBS Letters

Prijambada, Irfan D¹  Yamamoto, Keizo²  Ohhashi, Seiji¹  Yomo, Tetsuya¹  Urabe, Itaru¹  Shima, Yasufumi¹  Tanaka, Fumihiro¹  Kataoka, Mikio³  Ogasahara, Kyoko⁴  Yamauchi, Asao¹  Yutani, Katsuhide⁴ 

[1] Department of Biotechnology, Faculty of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565, Japan;Department of Chemistry, Nara Medical University, 840 Shijo, Kashihara, Nara 634, Japan;Department of Earth and Space Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560, Japan;Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565, Japan

关键词: Artificial protein;    Random sequence;    Enzyme evolution;    Circular dichroism spectrum;    Small-angle X-ray scattering;    Esterase activity;    TFE;    2;    2;    2-trifluoroethanol;   

DOI  :  10.1016/S0014-5793(97)01552-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The structural and catalytic properties of two soluble random proteins, RP3-42 and RP3-45, of 141 amino acid residues were investigated. Although no marked secondary structure was detected by CD spectrum, sedimentation equilibrium and small-angle X-ray scattering studies showed that they form an oligomeric structure and are as compact as the molten globule. The random proteins have low but distinct esterase activity; the values of the second-order rate constant for the hydrolysis of p-nitrophenol were 0.78 and 1.39 M⁻¹ s⁻¹ for RP3-42 and RP3-45, respectively. The differences in the properties of the random and the native proteins are discussed from the evolutionary point of view.

【 授权许可】

Unknown