Theory Study on Glycine Linear Oligopeptide Vibrational Spectrum Frequency Shift
YE Zhi-peng1, LI Xin1, YANG Meng-shi1, CHEN Liang2*, XU Can3, CHU Xiu-xiang2
1. School of Engineering, Zhejiang A&F University, Lin’an 311300, China 2. School of Science, Zhejiang A&F University, Lin’an 311300, China 3. Key Lab for Magnetism and Magnetic Materials of Ministry of Education，Lanzhou University, Lanzhou 730000, China
Abstract：By using the density functional theory, glycine linear oligopeptide of different lengths was geometrically optimized on the 6-31G (d) basis set level, their growth processes were simulated, and the average binding energy and vibration frequency were calculated with geometry. The results showed that the average binding energies tend to change in a regular pattern and stabilize with the number of residues increasing; With the oligopeptide chain bond length analysis it was found that the chain to the radial direction there is a opposite trend for chain and radial direction, which is anisotropic. It was found by the IR spectrum analysis that red shifts and blue shifts occur respectively when the same group of peptide bond vibrate, which is anisotropic; These phenomena originate from that quasi one-dimensional nanostructures lead to the anisotropy of the bond length; the induced effects, coupling effects and hydrogen bonding etc. between the same groups lead to the vibration frequency red shifts and blue shifts. The authors conclude that the growth of glycine linear oligopeptide is conducive to stability of the structure, and the authors infer that the oligopeptide has the tendency of self-assembled growth; Through the conformation and spectrum, the authors infer that there is a size effect in physical and chemical properties. The physical and chemical properties of peptide chain end group are extremely stable and unaffected by the impact of the oligopeptide chain length. The results are significant to measuring the length and the number of residue of peptide, and to manufacturing the special features oligopeptide chain.
叶志鹏1，李 鑫1，羊梦诗1，陈 亮2*，徐 灿3，储修祥2. 甘氨酸直链寡肽振动光谱频移现象的理论研究[J]. 光谱学与光谱分析, 2014, 34(04): 879-883.
YE Zhi-peng1, LI Xin1, YANG Meng-shi1, CHEN Liang2*, XU Can3, CHU Xiu-xiang2 . Theory Study on Glycine Linear Oligopeptide Vibrational Spectrum Frequency Shift. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2014, 34(04): 879-883.
