Characterization of the dimerization process of HIV‐1 reverse transcriptase heterodimer using intrinsic protein fluorescence

FEBS Letters

Goody, R.S.¹  Restle, T.¹  Divita, G.¹ 

[1] Max-Planck-Institut für medizinische Forschung, Abteilung Biophysik, Jahnstraße 29, 6900 Heidelberg, Germany

关键词: HIV;    Reverse transcriptase;    Dimerization;    Intrinsic protein fluorescence;    Gdn-HCl;    guanidinium hydrochloride;    HIV;    human immunodeficiency virus;    HPLC;    high-performance liquid chromatography;    RT;    reverse transcriptase;   

DOI  :  10.1016/0014-5793(93)81383-B

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Intrinsic protein fluorescence has been used to study dimerization of the HIV-1 reverse transcriptase (RT). We observed a 25% increase of the tryptophan fluorescence of the enzyme during dissociation of the subunits induced by the addition of acetonitrile. Upon reassociation of the separated subunits, the original fluorescence emission of the heterodimer is restored. A two-state transition model for the RT dimerization process in which the dimers are in equilibrium with folded monomers is proposed. The free energy of dissociation was determined to be 12.2 (± 0.2) kcal/mol. In the absence of Mg²⁺ ions a decrease of this value was observed, whereas the addition of a synthetic primer/template (18/36mer) results in an increase of dimer stability. Analyzing the effect of Mg²⁺ on the establishment of the binding equilibrium, a dramatic effect with a 100-fold acceleration of the association by the divalent ion was observed.

【 授权许可】

Unknown