CJCU

Chem. J. Chinese Universities ›› 1996, Vol. 17 ›› Issue (3): 451.

• Articles • Previous Articles     Next Articles

Terbium(Ⅲ) Luminescence Probes:Determination of Energy Transfer Distance Between Metal Ion and Tryptophan in Proteins and Postulation of Their Binding Sites

YANG Jing-He1, ZHAO Wei-Dong1, TONG Chang-Lun1, JIE Nian-Qin1, ZHANG Gui-Ling1, GAO Zu-Quan2   

  1. 1. College of Chemistry, Shandong University, Jinan 250100;
    2. Department of Biology, Shandong University, Jinan 250100
  • Received:1995-03-02 Online:1996-03-24 Published:1996-03-24

PDF (PC)

Abstract: The luminescence properties of the complex of Tb(Ⅲ)with bovine pancreatic deoxyribonuclease(BPD),bacillus subtilis α-amylase(BSα-A) were studied by using the fluorescence method.It was found that BPD, BSα-Acan coordinated with Tb(Ⅲ)at pH=7～8 and 5～6 respectively, and then emits a strong characteristic fluorescence of Tb(Ⅲ).The complex ratios for Tb (Ⅲ) and BPD, BSα-Awere 2:1 and 4:1 respectively.In this paper,Forster theory was used to determine the energy transfer distance between BPD,BSα-Aenergy-donor and Tb (Ⅲ) energy-acceptor.The values of the critical distance for 50% energy transfer,R0,of 0.336 nm and 0.390 nm were obtained.The donor-acceptor energy transfer distances,R,estimated from the measured efficiency were 1.39 nm,1.48 nm respectively.It is inferred that the binding sites between Tb (Ⅲ) and BPD, BSα-Awere Trp-178, Trp-188 and Trp-321,respectively.

Key words: Terbium luminescence, Energy transfer distance, Binding sites

TrendMD: