[Study on the non-covalent interaction of 7-hydroxy flavone and its phosphate with DNA by fluorescence method].
The non-covalent interaction of 7-hydroxy flavone and its phosphate with DNA was studied using ethidium bromide (EB)as a probe. The result showed that both 7-hydroxy flavone and its phosphate could form non-covalent complexes, but the phosphorylated flavonoid showed higher binding affinity with DNA than 7-hydroflavone did. Experiments demonstrated that the higher the temperature, the lower the slop of quenching curve of DNA-EB in the presence of different amounts of 7-hydroxy flavone and its phosphate. It was confirmed that the combinations of DNA with 7-hydroxy flavone and its phosphate were a single static quenching process. According to the Stern-Volmer equation and Scatchard equation the quenching constants and the intrinsic binding constants of 7-hydroxy flavone and its phosphate were measured respectively, they were Kq1 = 601 L x mol(-1), Kq2 = 1381 L x mol(-1); K1 = 2.07 x 10(4) L x mol(-1) , K2 = 3.19 x 10(4) L x mol(-1) respectively.
Guo
Yu-hua
YH
Key Laboratory for Bio-Chemistry and Organic Chemistry, Zhengzhou University, Zhengzhou 450052, China.
Chen
Xiao-lan
XL
Zhang
Ting
T
Qu
Ling-Bo
LB
Zhao
Yu-fen
YF
Yu
You-zhu
YZ
D000818:Animals; D002417:Cattle; D004247:DNA / Q000737:chemistry*; D004996:Ethidium / Q000031:analogs & derivatives / Q000737:chemistry; D005419:Flavonoids / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013056:Spectrophotometry, Ultraviolet
D005419:Flavonoids; D010710:Phosphates; C052890:ethidium-DNA complex; D004247:DNA; C427203:calf thymus DNA; D004996:Ethidium; C429845:7-hydroxyflavone