纤维二糖酶在不同pH下的拉曼光谱分析

Raman Spectral Analysis of Cellobiase at Various pH

分析了绿色木霉产的纤维二糖酶在pH 5.0和pH 2.0下的拉曼光谱图。实验结果表明:纤维二糖酶在pH 5.0时具有酶活功能,蛋白主链结构主要为α-螺旋和无规则卷曲,侧链中酪氨酸和色氨酸均为"埋藏式";纤维二糖酶在pH 2.0时无酶活,酶蛋白主链结构主要为α-螺旋,而无规则卷曲发生较大变化,铡链中的酪氨酸和色氨酸均为"暴露式"。根据光谱特征分析,该纤维二糖酶中可能不含二硫键。

Cellobiase is a component of cellulase complex produced by Trichoderrna viride in shake flask culture. The characterization of Raman spectra of cellobiase solution at pH 5.0 and pH 2.0 was analyzed. It shows that under pH 5.0 the primary chain structure of cellobiase with catalysis activity exhibits α-helical and disordered structure, and in the branch chain of cellobiase tyrosine and tryptophan are ＂buried＂, whereas, under pH 2.0, the principal chain structure of cellobiase without catalysis activity exhibits only α-helical, and tyrosine and tryptophan in the branch chain of cellobiase are ＂exposed＂. It is inferred that cellobiase produced by Trichoderrna viride does not contain S-S stretching based on its Raman spectral data.