Effect of the C-terminal domain of Vibrio proteolyticus chitinase A on the chitinolytic activity in association with pH changes
Effect of the C-terminal domain of Vibrio proteolyticus chitinase A on the chitinolytic activity in association with pH changes
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解蛋白弧菌几丁质酶 A 的 C 末端结构域对与 pH 变化相关的几丁质分解活性的影响
DOI：
10.1111/j.1472-765x.2012.03228.x
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发表时间：
2012
影响因子：
2.4
通讯作者：
S. Itoi
中科院分区：
文献类型：
--
作者：
H. Sugita;H. Mizuki;S. Itoi;B. Techaratanakrai・岡崎惠美子・大迫一史;S. Itoi
目的：为了揭示溶蛋白弧菌几丁质酶 A 与卡卡氏弧菌（哈维氏弧菌的初级同义词）菌株几丁质酶 A 活性差异的原因，我们研究了全长 V 的 pH 依赖性活性。蛋白水解几丁质酶A和对应于V的截短重组体。方法与结果：在大肠杆菌DH5α中过表达后，通过硫酸铵沉淀和阴离子交换柱层析纯化全长和截短的重组几丁质酶。使用 α 晶体和胶体几丁质作为底物，在不同 pH 值下测量几丁质酶活性。 α-晶体几丁质的相对比活性的 pH 依赖性模式在全长和截短的重组几丁质酶之间有所不同，而胶体几丁质的相对比活性的 pH 依赖性模式彼此相似。结论：V 的活性存在差异。蛋白水解几丁质酶 A 和 V。哈维几丁质酶 A 的部分原因可能是由于 C 末端加工导致几丁质酶活性对 α 晶体几丁质的 pH 依赖性发生变化。 研究的意义和影响：本研究结果不仅对于弧菌属与生存策略相关的生态学研究，而且对于系统发育研究都是重要的发现。
Aims:To reveal the cause of the difference in activity of chitinase A fromVibrio proteolyticusand chitinase A from a strain ofVibrio carchariae(a junior synonym ofVibrio harveyi), we investigated the pH‐dependent activity of full‐lengthV. proteolyticuschitinase A and a truncated recombinant corresponding to theV. harveyiform of chitinase A.Methods and Results:After overexpression inEscherichia colistrain DH5α, the full‐length and truncated recombinant chitinases were purified by ammonium sulphate precipitation and anion exchange column chromatography. Chitinase activity was measured at various pH values using α‐crystal and colloidal chitins as the substrate. The pH‐dependent patterns of the relative specific activities for α‐crystal chitin differed between the full‐length and truncated recombinant chitinases, whereas those for colloidal chitin were similar to each other.Conclusion:The difference in the activity ofV. proteolyticuschitinase A andV. harveyichitinase A might be partly due to a change in the pH dependence of the chitinase activities against α‐crystal chitin, resulting from C‐terminal processing.Significance and Impact of Study:The present results are important findings for not only ecological studies on the genusVibrioin association with survival strategies, but also phylogenetic studies.