一种中国林蛙抗菌肽的光谱研究

从中国林蛙皮中纯化得到了一种抗多种临床多重耐药菌的抗菌肽(RTCⅠ), 初步氨基酸组成分析结果表明其不含碱性氨基酸, 此抗菌肽在276.5和356.5 nm波长光的激发下发射出448 nm的荧光, 利用傅里叶变换红外光谱、拉曼光谱、电子吸收光谱及荧光光谱等技术研究了此特定荧光产生的结构依据. 此抗菌肽的主要组成是Tyr, Asn(Asp)和Glu(Gln), 抗菌肽特殊的荧光光谱和电子吸收谱与Tyr的酚羟基和Asn侧链的强氢键有关. 这一特殊的荧光(448 nm)及圆二色谱(259, 263和267 nm)信号为进一步在分子水平上研究此抗菌肽的抗菌机理提供了依据.

Spectroscopic Characterization of An Antimicrobial Peptide(RTCⅠ) from Skin of Rana temporaria chensinensis, David

An anion antimicrobial peptide(RTCⅠ) was purified from skin of Rana temporaria chensinensis, David, which has an antimicrobial activity against many strains of clinical multi-drug resistant bacteria. When excited at 276.5 and 356.5 nm, it exhibited a single emission band(λmax=448 nm). IR spectroscopy, Raman spectroscopy, fluorescence spectroscopy and amino acid composition analysis were used to study the structure basis of the characters observed in fluorescence spectra. Tyr, Asn(Asp) and Glu(Gln) are the mainly amino acid composition of RTCⅠ, it is suspected that the specific fluorescence spectra and electronic absorbance spectra are related to the strong hydrogen bond of Tyr phenolic hydroxyl groups and the side chains of Asn. The peculiar fluorescence will provide the possibility for further studies of the antibacterial mechanism on molecular level.