Dissociation constants and thermal stability of complexes of Bacillus intermedius RNase and the protein inhibitor of Bacillus amyloliquefaciens RNase

FEBS Letters

Yakovlev, G.I.¹  Hartley, R.W.²  Bocharov, A.L.¹  Moiseyev, G.P.¹  Ranjbar, B.¹  Briand, C.M.³  Makarov, A.A.¹  Protasevich, I.I.¹  Gilli, R.M.³  Kirpichnikov, M.P.¹ 

[1] Engelhardt Institute of Molecular Biology, Acad. Sci. Russia, Moscow 117984, Russian Federation;National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda 20892, USA;CNRS URA 1924, Université d'Aix-Marseille II, Marseille 13385, France

关键词: Binase-barstar complex;    Dissociation constant;    Heat denaturation;    Scanning microcalorimetry;    Isothermal microcalorimetry;   

DOI  :  10.1016/0014-5793(95)00491-Q

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Binase, the extracellular ribonuclease of Bacillus intermedius, is inhibited by barstar, the natural protein inhibitor of the homologous RNase, barnase, of B. intermedius. The dissociation constants of the binase complexes with barstar and its double Cys^40.82 Ala mutant are about 10⁻¹² M, only 5 to 43 times higher than those of the barnase-barstar complex. As with barnase, the denaturation temperature of binase is raised dramatically in the complex. Calorimetric studies of the formation and stability of the binase-barstar complex show that the binase reaction with barstar is qualitatively similar to that of barnase but some significant quantitative differences are reported.

【 授权许可】

Unknown