Biochemical characterisation of the neuraminidase pool of the human gut symbiont Akkermansia muciniphila
Biochemical characterisation of the neuraminidase pool of the human gut symbiont Akkermansia muciniphila
复制标题
人肠道共生体 Akkermansia Muciniphila 神经氨酸酶库的生化特征
DOI：
10.1016/j.carres.2015.08.001
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发表时间：
2015-10-13
影响因子：
3.1
通讯作者：
Voglmeir, Josef
中科院分区：
文献类型：
--
作者：
Huang, Kun;Wang, Mao M.;Voglmeir, Josef
自十年前分离和鉴定嗜粘蛋白阿克曼菌以来，这种肠道细菌因其在肥胖和2型糖尿病中的作用而引起了人们的广泛关注。本报告描述了A.粘蛋白体基因组。被指定为Am 0705、Am 0707、Am 1757和Am 2085的特异性表达的候选基因显示覆盖4.0和9.5之间的互补pH范围。酶的最适温度在37至42摄氏度之间。所有四种酶强烈抑制Cu 2+和Zn 2+，和添加EDTA后的活性损失表明，所有的神经氨酸酶，除了Am 0707，需要二价金属离子为它们的催化功能。利用化学酶促合成的α 2，3-和α 2，6-连接的吲哚酰-唾液酸糖苷来确定神经氨酸苷酶对唾液酸与N-乙酰基-、N-羟乙酰基-、N-丙酰基-或羟基-基团的C5-修饰的区域选择性和底物混杂性。简单的纯化程序和良好的活动的一些特征的神经氨酸酶的组合，使他们潜在的有趣的生物分析或工业应用的工具。(C)2015爱思唯尔有限公司版权所有。
Since the isolation and identification of Akkermansia muciniphila one decade ago, much attention has been drawn to this gut bacterium due to its role in obesity and type 2 diabetes. This report describes the discovery and biochemical characterisation of all four putative neuraminidases annotated in the A. muciniphila genome. Recombinantly expressed candidate genes, which were designated Am0705, Am0707, Am1757 and Am2085, were shown to cover complementary pH ranges between 4.0 and 9.5. Temperature optima of the enzymes lay between 37 and 42 degrees C. All four enzymes were strongly inhibited by Cu2+ and Zn2+, and loss of activity after the addition of EDTA suggests that all neuraminidases, with the exception of Am0707, require divalent metal ions for their catalytic function. Chemoenzymatically synthesised alpha 2,3- and alpha 2,6-linked indoyl-sialosides were utilised to determine the regioselectivity and substrate promiscuity of the neuraminidases towards C5-modifications of sialic acids with N-acetyl-, N-glycolyl-, N-propionyl-, or hydroxyl-groups. The combination of simple purification procedures and good activities of some of the characterised neuraminidases makes them potentially interesting as tools in bioanalytical or industrial applications. (C) 2015 Elsevier Ltd. All rights reserved.