A chitin deacetylase from the endophytic fungus Pestalotiopsis sp. efficiently inactivates the elicitor activity of chitin oligomers in rice cells.
A chitin deacetylase from the endophytic fungus Pestalotiopsis sp. efficiently inactivates the elicitor activity of chitin oligomers in rice cells.
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DOI：
10.1038/srep38018
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发表时间：
2016-11-30
影响因子：
4.6
通讯作者：
Moerschbacher BM
中科院分区：
文献类型：
--
作者：
Cord-Landwehr S;Melcher RL;Kolkenbrock S;Moerschbacher BM
为了在植物中成功存活，内生菌需要策略来避免被植物免疫系统检测到，因为内生菌的细胞壁含有容易检测的几丁质。内生菌可能通过使用几丁质脱乙酰酶（CDA）修饰几丁质或衍生自几丁质的低聚物来“隐藏”这种几丁质以使其不被植物免疫系统所知。为了探索这一假说，我们从内生真菌拟盘多毛孢（Pestalotiopsis sp.，PesCDA）中鉴定并表达了一个CDA。大肠杆菌中，并表征了该酶及其壳聚糖低聚物产物。我们发现，当PesCDA修饰甲壳素低聚物时，产物是具有特定乙酰化模式的部分脱乙酰化的壳聚糖低聚物：GlcNAc-GlcNAc-（GlcN）n-GlcNAc（n ≥ 1）。然后，在生物活性测定中，悬浮培养的水稻细胞与PesCDA产品（加工几丁质六聚体）一起孵育，我们发现，与底物六聚体不同，壳聚糖低聚物产品不再引起植物免疫系统。因此，这种内生酶可以防止内生菌被植物免疫系统识别;这可能代表了某些真菌如何能够生活在宿主体内或宿主上的更普遍的假设。
To successfully survive in plants, endophytes need strategies to avoid being detected by the plant immune system, as the cell walls of endophytes contain easily detectible chitin. It is possible that endophytes “hide” this chitin from the plant immune system by modifying it, or oligomers derived from it, using chitin deacetylases (CDA). To explore this hypothesis, we identified and expressed a CDA from Pestalotiopsis sp. (PesCDA), an endophytic fungus, in E. coli and characterized this enzyme and its chitosan oligomer products. We found that when PesCDA modifies chitin oligomers, the products are partially deacetylated chitosan oligomers with a specific acetylation pattern: GlcNAc-GlcNAc-(GlcN)n-GlcNAc (n ≥ 1). Then, in a bioactivity assay where suspension-cultured rice cells were incubated with the PesCDA products (processed chitin hexamers), we found that, unlike the substrate hexamers, chitosan oligomer products no longer elicited the plant immune system. Thus, this endophytic enzyme can prevent the endophyte from being recognized by the plant immune system; this might represent a more general hypothesis for how certain fungi are able to live in or on their hosts.
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影响因子：
4.6
作者：
Hamer SN;Cord-Landwehr S;Biarnés X;Planas A;Waegeman H;Moerschbacher BM;Kolkenbrock S
通讯作者：
Kolkenbrock S
影响因子：
11.2
作者：
Cai, Jun;Yang, Jianhong;Kennedy, John F.
通讯作者：
Kennedy, John F.
影响因子：
3.1
作者：
Hamer, Stefanie Nicole;Moerschbacher, Bruno Maria;Kolkenbrock, Stephan
通讯作者：
Kolkenbrock, Stephan
影响因子：
5.6
作者：
Jones, DT
通讯作者：
Jones, DT
影响因子：
2.9
作者：
Blair, David E.;Hekmat, Omid;van Aalten, Daan M. F.
通讯作者：
van Aalten, Daan M. F.