偏最小二乘红外光谱法及其对三种过氧化氢酶二级结构的测定

DETERMINATION OF THE SECONDARY STRUCTURE OF THREE CATALASES USING THE PARTIAL LEAST-SQUARES INFRARED METHOD

以九种蛋白质及其晶体结构数据为校准，建立了蛋白质二级结构测定的偏最小二乘红外光谱定量法，并分析了三种过氧化氢酶在水溶液中的二级结构。结果表明本法对于测定水溶液中二级结构是一种简便、有效、准确和可靠的方法。

The secondary structure of three catalases in water solution was determined using the established partial least-squares (PLS) infrared method which is based on nine proteins of known crystal structures. The optimum standard deviation of the difference between X-ray and PLS infrared estimates is 3. 8% for a-helix,3. 8% for β-sheet and 4. 9% for undefined structure, whereas at rank=4, the regression coefficients are 0. 997, 0. 995 and 0. 996, respectively. The result showed that the secondary structural content of catalase from Micrococcus lysodeikticus (MLC) is different from that of beef liver and Aspergillusniger, which may provide an explanation of the special catalytic activity of MLC on organophosphorous toxicants.