Discovery of a Bacterial Glycoside Hydrolase Family 3 (GH3) β-Glucosidase with Myrosinase Activity from a Citrobacter Strain Isolated from Soil
Discovery of a Bacterial Glycoside Hydrolase Family 3 (GH3) β-Glucosidase with Myrosinase Activity from a Citrobacter Strain Isolated from Soil
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DOI：
10.1021/acs.jafc.5b05381
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发表时间：
2016-02-24
影响因子：
6.1
通讯作者：
Rossiter, John T.
中科院分区：
文献类型：
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作者：
Albaser, Abdulhadi;Kazana, Eleanna;Rossiter, John T.
以芥子油苷为唯一碳源，从英国土壤中分离得到一株柠檬酸杆菌属菌株WYE 1。使用离子交换和凝胶过滤的组合纯化黑芥子酶，得到约66 kDa的纯蛋白质。确定纯化蛋白的N-末端氨基酸和内部肽序列，并用于鉴定基因，其基于InterPro序列分析，属于家族GH 3，含有信号肽，并且是预测分子量为71.8 kDa的周质蛋白。使用来自无细胞制剂的蛋白质提取物进行初步表征。以黑芥子苷为底物，表观K-M和V-max分别为0.46 mM和4.91 mmol dm（-3）min（-1）mg（-1）。该酶的最适温度为25 ℃，最适pH为6.0。该酶与抗坏血酸的激活因子为1.67。
A Citrobacter strain (WYE1) was isolated from a UK soil by enrichment using the glucosinolate sinigrin as sole carbon source. The enzyme myrosinase was purified using a combination of ion exchange and gel filtration to give a pure protein of approximately 66 kDa. The N-terminal amino acid and internal peptide sequence of the purified protein were determined and used to identify the gene, which, based on InterPro sequence analysis, belongs to the family GH3, contains a signal peptide, and is a periplasmic protein with a predicted molecular mass of 71.8 kDa. A preliminary characterization was carried out using protein extracts from cell-free preparations. The apparent K-M and V-max were 0.46 mM and 4.91 mmol dm(-3) min(-1) mg(-1), respectively, with sinigrin as substrate. The optimum temperature and pH for enzyme activity were 25 degrees C and 6.0, respectively. The enzyme was marginally activated with ascorbate by a factor of 1.67.