Department of Biochemistry, Maria Curie-Skłodowska University, Akademicka 19 St., 20-033 Lublin, Poland.
Enzyme Microb Technol. 2013 Dec 10;53(6-7):427-37. doi: 10.1016/j.enzmictec.2013.09.007. Epub 2013 Sep 25.
Cellobiose dehydrogenase (CDH), an extracellular flavocytochrome produced by several wood-degrading fungi, was detected in the culture supernatant of the selective delignifier Pycnoporus sanguineus maintained on a cellulose-based liquid medium. Cellobiose dehydrogenase was purified as two active fractions: CDH1-FAD (flavin domain) (40.4 fold) with recovery of 10.9% and CDH1 (flavo-heme enzyme) (54.7 fold) with recovery of 9.8%. As determined by SDS-PAGE, the molecular mass of the purified enzyme was found to be 113.4kDa and its isoelectric point was 4.2, whereas these values for the FAD-domain were 82.7kDa and pI=6.7. The carbohydrate content of the purified enzymes was 9.2%. In this work, the cellobiose dehydrogenase gene cdh1 and its corresponding cDNA from fungus P. sanguineus were isolated, cloned, and characterized. The 2310bp full-length cDNA of cdh1 encoded a mature CDH protein containing 769 amino acids, which was preceded by a signal peptide of 19 amino acids. Moreover, both active fractions were characterized in terms of kinetics, temperature and pH optima, and antioxidant properties.
纤维二糖脱氢酶（CDH）是一种由几种木质素降解真菌产生的细胞外黄素细胞色素，在选择性木质素降解菌 Pycnoporus sanguineus 维持在基于纤维素的液体培养基中的培养上清液中被检测到。纤维二糖脱氢酶被纯化为两个活性部分：CDH1-FAD（黄素结构域）（40.4 倍），回收率为 10.9%，CDH1（黄素-血红素酶）（54.7 倍），回收率为 9.8%。通过 SDS-PAGE 确定，纯化酶的分子量为 113.4kDa，等电点为 4.2，而 FAD 结构域的这些值分别为 82.7kDa 和 pI=6.7。纯化酶的碳水化合物含量为 9.2%。在这项工作中，从真菌 P. sanguineus 中分离、克隆和表征了纤维二糖脱氢酶基因 cdh1 及其相应的 cDNA。全长为 2310bp 的 cdh1 cDNA 编码一个成熟的 CDH 蛋白，包含 769 个氨基酸，其前面有 19 个氨基酸的信号肽。此外，还从动力学、温度和 pH 最佳条件以及抗氧化特性方面对两个活性部分进行了表征。
