The studies of cooperative regions in T7 RNA polymerase

FEBS Letters

Memelova, L.V.¹  Makarov, A.A.¹  Kochetkov, S.N.¹  Protasevich, I.I.¹ 

[1] Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilov str. 32, Moscow 117984, Russian Federation

关键词: Bacteriophage T7 RNA polymerase;    Heat denaturation;    Scanning microcalorimetry;    Domain structure;    T7RNAP;    bacteriophage T7 DNA-dependent RNA polymerase;   

DOI  :  10.1016/0014-5793(94)00718-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The heat denaturation of bacteriophage T7 RNA polymerase (T7RNAP) was studied by scanning microcalorimetry. The thermodynamic parameters of the denaturation were estimated within the pH range 6–9. The analysis of the denaturation curves showed the presence of two cooperative parts of the T7RNAP molecule melting according to the ‘all-or-none’ principle. The molecular masses of these parts were determined as 22 and 77 kDa. These values are close to the molecular masses of protein domains obtained from X-ray diffraction and limited trypsinolysis data. The smaller N-terminal domain was shown to increase the thermostability of the ‘catalytic’ C-terminal domain within the intact T7RNAP molecule.

【 授权许可】

Unknown