Directional degradation of β‐chitin by chitinase A1 revealed by a novel reducing end labelling technique
Directional degradation of β‐chitin by chitinase A1 revealed by a novel reducing end labelling technique
复制标题
新型还原端标记技术揭示了几丁质酶 A1 定向降解 β-几丁质
DOI：
10.1016/s0014-5793(01)03249-5
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发表时间：
2002
期刊：
影响因子：
3.5
通讯作者：
J. Sugiyama
中科院分区：
文献类型：
--
作者：
T. Imai;Takeshi Watanabe;T. Yui;J. Sugiyama
建立了一种新的β-甲壳素晶体分子末端标记方法。通过在甲壳素链的还原端引入生物素的酰肼衍生物，然后通过生物素与链霉亲和素之间的特异性相互作用以及胶体金颗粒，可以通过透射电子显微镜直接观察β-甲壳素微晶的链方向性。该方法可以证明β-甲壳素微晶中甲壳素链的平行性，也可以标记被环状芽孢杆菌几丁质酶A1降解的β-甲壳素微晶的还原尖端。对于这些底物，标记仅发生在其锥形尖端，这表明这些晶体的消化从其还原端开始。这种新的标记方法的推广到其他多糖晶体进行了讨论。
A novel procedure for labelling the molecular ends of β‐chitin crystals has been established. By introducing a hydrazide derivative of biotin at the reducing end of a chitin chain, followed by a specific interaction between biotin and streptavidin coupled with a colloidal gold particle, the chain directionality of β‐chitin microcrystals could be directly visualized by transmission electron microscopy. This method allowed to certify the parallelism of the chitin chains in the β‐chitin microcrystals, and also to label the reducing tips of β‐chitin microcrystals degraded byBacillus circulanschitinase A1. With these substrates, the labelling occurred only at their tapered tip, which indicates that the digestion of these crystals proceeded from their reducing end. The generalization of this new labelling method to other polysaccharide crystals is discussed.