Analysis of Poly(dA) center dot Polv(dT) structure by Raman spectroscopy and lattice dynamics

作者：Meng YY^*; Liu SH

来源：Spectroscopy and Spectral Analysis, 2000, 20(3): 280-282.

• poly(dA) center dot poly(dT)
• structure analysis
• raman spectroscopy
• lattice dynamics

Poly(dA).poly( dT) is a kind of DNA which one strand contains adenine(A) bases,and the other only thymine(T) bases. This DNA possesses flexible structure and the X-ray diffraction for poly(dA).poly( dT) fiber gives three different structures. So it is of interest to study poly( dA).poly( dT) structure in solution. In this paper,Raman spectrum of poly(dA).poly(dT) in 0.2 mol.L-1 NaCl solution was recorded over the spectral range 750-1 000 cm(-1). The Raman bands at 817 cm(-1) and 813 cm(-1) exist simultaneously. This implied that the secondary structure of poly(dPL).poly(dr) is neither A-conformation nor B.conformation. Normal mode analysis of heteronomous secondary structure from poly(dA).poly(dT) fibers was carried out by the lattice dynamics. Normal modes were assigned by potential energy distribution (PED). The calculated frequencies are good agreement with the observed Raman spectrum. This indicated that poly(dA).poly(dT) in solution probably has the same structure as poly(dA).poly(dT) fiber, namely the poly(dA) chain has the GS'-endo ring pucker while the poly(dT) chain has the C2'-endo ring pucker.

• 出版日期2000-6
• 单位华南师范大学