通过聚丙烯酰胺凝胶电泳和傅里叶变换红外光谱研究了高压脉冲电场(PEF)处理对大肠杆菌(E.coli)胞内蛋白的影响,并应用去卷积和曲线拟合等数学方法和圆二(CD)色谱进一步分析PEF处理前后蛋白二级结构中α-螺旋、β-转角、β-折叠和无规卷曲相对含量的变化。结果表明,经过PEF(30 kV/cm,400μs)处理后,在分离胶的顶端出现了蛋白质的聚集。蛋白二级结构中β-折叠相当含量从45.40%降至21.50%,β-转角相对含量从23.8%降至8.81%,而无规卷曲结构从0.13%升至36.95%,α-螺旋结构没有明显的变化。

The effects of pulsed electric fields(PEF) on the structures of intracellular proteins of E.coli were investigated by SDS-PAGE analysis and FTIR.The original spectrum was dissolved by Fourier self-deconvolution and curve-fitting to show the peaks of the α-helix,β-turn,random coil and β-sheet in combination with CD spectrum.The results showed PEF treatments(30 kV/cm,400μs)can induce the formation of aggregates.The contents of β-sheet decreased from 45.40% to 21.50% and the contents of β-turn decreased from 23.80% to 8.81%,while the contents of random coil increased from 0.13% to 36.95%.The contents of α-helix changes insignificantly.