Two‐stage thermal unfolding of [Cys55]‐substituted Cro repressor of bacteriophage λ

FEBS Letters

Kutyshenko, V.P.²  Gitelson, G.I.¹  Privalov, P.L.¹  Griko, Yu.V.¹  Rogov, V.V.¹  Kurochkin, A.V.³  Kirpichnikov, M.P.³ 

[1] Institute of Protein Research, Academy of Sciences of the USSR, Pushchino, Moscow Region 142292, USSR;Institute of Biological Physics, Academy of Sciences of the USSR, Pushchino, Moscow Region 142292, USSR;V.A. Engelhardt Institute of Molecular Biology, Academy of Sciences of the USSR, Moscow 117984, USSR

关键词: Cro repressor;    Mutant;    Thermal denaturation;    S–S bond;    Scanning calorimetry;    1H NMR;   

DOI  :  10.1016/0014-5793(91)81069-K

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

It has been shown by scanning calorimetry and ¹H NMR spectroscopy that thermal denaturation of mutant λ phage cro repressor in which Val⁵⁵ was substituted for Cys, proceeds in 2 stages in contrast to the wild type protein. At neutral pH values, an additional cooperative transition has been observed at about 100°C. Calorimetric measurements on the mutant and its tryptic fragment lead to the conclusion that the two-stage character of thermal unfolding of the mutant is due to a disruption of an additional cooperative domain in the dimer molecule which is stabilized by the S–S crosslink.

【 授权许可】

Unknown