期刊
BIOCATALYSIS AND BIOTRANSFORMATION
卷 26, 期 1-2, 页码 120-127出版社
TAYLOR & FRANCIS LTD
DOI: 10.1080/10242420701789320
关键词
pyranose oxidase; enzyme engineering; substrate specificity; galactose oxidation
Site-directed mutagenesis was used to enhance the catalytic activity of pyranose 2-oxidase (P2Ox) from Trametes multicolor with different substrates. To this end, threonine at position 169 was replaced by glycine, alanine and serine, respectively. Using oxygen as electron acceptor the mutant T169G was equally active with d-glucose and d-galactose, whereas wild-type recombinant P2Ox only showed 5.2% relative activity with the latter substrate. When d-galactose was used as electron donor in saturating concentrations, T169G showed a 4.5-fold increase in its catalytic efficiency k(cat)/K-M for the alternative electron acceptor 1,4-benzoquinone and a nine-fold increased k(cat)/K-M value with the ferricenium ion compared with wt recP2Ox. Variant T169S showed an increase in its catalytic efficiency both with 1,4-benzoquinone (3.7 times) as well as with the ferricenium ion (1.4 times) when D-glucose was the substrate.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据