In vivo non‐specific binding of λ CI and Cro repressors is significant

FEBS Letters

Metzler, Ralf¹  Bakk, Audun¹ 

[1] NORDITA, Blegdamsvej 17, DK-2100 Copenhagen, Denmark

关键词: Genetic regulation;    Lambda phage;    Non-specific binding;    Thermodynamics;    O R;    right operator;    ΔG;    Gibbs free energy difference;    RNAP;    RNA polymerase;    NSB;    non-specific binding;    O L;    left operator;   

DOI  :  10.1016/S0014-5793(04)00249-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We propose a thermodynamic model that includes the non-specific binding of the λ phage regulatory proteins CI and Cro. By fitting the model to experimental in vivo data on activities of the two promoters P _RM and P _R versus concentration, we estimate the free energy upon non-specific binding to be −4.1±0.9 kcal/mol for CI and −4.2±0.8 kcal/mol for Cro. For concentrations >100 nM of CI or Cro, we find that >50% of these proteins are non-specifically bound. In particular, in a lysogen (∼250 CI monomeric equivalents per cell) nearly 90% of CI is non-specifically bound.

【 授权许可】

Unknown