Characterization of a multi-function processive endoglucanase CHU_2103 from Cytophaga hutchinsonii
Characterization of a multi-function processive endoglucanase CHU_2103 from Cytophaga hutchinsonii
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来自哈钦森细胞噬菌体的多功能加工内切葡聚糖酶 CHU_2103 的表征
DOI：
10.1007/s00253-014-5640-8
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发表时间：
2014-03
影响因子：
5
通讯作者：
Lu, Xuemei
中科院分区：
文献类型：
--
作者：
Zhou, Xiangru;Zhang, Weican;Zhao, Yue;Lu, Xuemei
HutchinsoniCytophaga hutchinsonii是一种革兰氏阴性滑行细菌，它能以未知的策略有效地降解结晶纤维素。基因组分析表明，华支睾吸虫基因组与一种明显的外切葡聚糖酶缺乏同源性，而这种酶以前似乎对纤维素降解至关重要。其中一种可能的内切葡聚糖酶CHU_2103在大肠杆菌JM109中成功表达，经鉴定为具有转糖活性的过程性内切葡聚糖酶。它能将羧甲基纤维素(CMC)水解成纤维糊精，并能迅速降低CMC的粘度。当CHU_2103降解再生无定形纤维素(RAC)时，3h后可溶/不溶还原糖比为3.72，主要产物为纤维二糖和纤维三糖，表明CHU_2103是一种连续的内切葡聚糖酶。Chu_2103能降解聚合度为≥3的纤维糊精。它通过从非还原端切割葡萄糖或纤维二糖来降解对-硝基苯基β-D-纤维糊精。同时，还检测到一些较大分子量的纤维糊精，表明其也具有糖基化活性。在没有碳水化合物结合模块(CBM)的情况下，CHU_2103可以与结晶纤维素结合，并对其进行连续作用。CHU_2103的定点突变表明，催化区保守的芳香族氨基酸W197不仅对其过程活性是必需的，而且对其与纤维素的结合能力也是必不可少的。
Cytophaga hutchinsonii is a Gram-negative gliding bacterium which can efficiently degrade crystalline cellulose by an unknown strategy. Genomic analysis suggests the C. hutchinsonii genome lacks homologs to an obvious exoglucanase that previously seemed essential for cellulose degradation. One of the putative endoglucanases, CHU_2103, was successfully expressed in Escherichia coli JM109 and identified as a processive endoglucanase with transglycosylation activity. It could hydrolyze carboxymethyl cellulose (CMC) into cellodextrins and rapidly decrease the viscosity of CMC. When regenerated amorphous cellulose (RAC) was degraded by CHU_2103, the ratio of the soluble to insoluble reducing sugars was 3.72 after 3 h with cellobiose and cellotriose as the main products, indicating that CHU_2103 was a processive endoglucanase. CHU_2103 could degrade cellodextrins of degree of polymerization ≥3. It hydrolyzed p-nitrophenyl β-D-cellodextrins by cutting glucose or cellobiose from the non-reducing end. Meanwhile, some larger-molecular-weight cellodextrins could be detected, indicating it also had transglycosylation activity. Without carbohydrate-binding module (CBM), CHU_2103 could bind to crystalline cellulose and acted processively on it. Site-directed mutation of CHU_2103 demonstrated that the conserved aromatic amino acid W197 in the catalytic domain was essential not only for its processive activity, but also its cellulose binding ability.
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影响因子：
2.8
作者：
M. Teunissen;A. A. M. Smits-A.;H. J. M. Op den Camp;J. H. J. Huis in't Veld-J.-H.-J.-Huis-in't-Veld-2257828295;G. D. Vogels
通讯作者：
M. Teunissen;A. A. M. Smits-A.;H. J. M. Op den Camp;J. H. J. Huis in't Veld-J.-H.-J.-Huis-in't-Veld-2257828295;G. D. Vogels
影响因子：
4.8
作者：
Kurasin, Mihhail;Vaeljamaee, Priit
通讯作者：
Vaeljamaee, Priit
影响因子：
3.2
作者：
C. Reverbel‐Leroy;S. Pagès;A. Bélaich;J. Belaich;C. Tardif
通讯作者：
C. Reverbel‐Leroy;S. Pagès;A. Bélaich;J. Belaich;C. Tardif
从纤维素分解细胞哈钦森噬菌体外膜分离的家族 5 糖苷水解酶的表征
影响因子：
5
作者：
Bi, Yanlin;Zhang, Weixin;Chen, Guanjun;Liu, Weifeng
通讯作者：
Liu, Weifeng
DOI：
10.1042/bj0320031
发表时间：
1938
期刊：
The Biochemical journal
影响因子：
--
作者：
Ernest Walker;Frederick Lloyd Warren
通讯作者：
Ernest Walker;Frederick Lloyd Warren