College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, P. R. China.
Can J Microbiol. 2009 Nov;55(11):1267-74. doi: 10.1139/w09-076.
Cell-wall chitin biosynthesis in the phytopathogenic fungus Botrytis cinerea involves 7 classes of chitin synthases. In this study, we disrupted a gene encoding a chitin synthase with a myosin-like motor domain (BcchsV) through Agrobacterium tumefaciens mediated transformation. The resulting mutant was not significantly affected in either growth characteristics or pathogenicity on tomato leaves. Surprisingly, the BcchsV mutant exhibited a 31% (m/m) increase in its chitin content compared with the wild-type strain. In addition, the BcchsV mutant showed increased sensitivity to Calcofluor White and slightly enhanced tolerance to cell-wall disturbing substances and osmosis regulators, including SDS, sorbitol, and NaCl. These results suggest that Bcchs does not play an essential role in the synthesis of cell-wall chitin in B. cinerea. However, disruption of this gene provoked a compensatory mechanism regulating the cellular response to cell-wall damage.
在植物病原菌 Botrytis cinerea 中，细胞壁几丁质的生物合成涉及 7 类几丁质合成酶。在这项研究中，我们通过农杆菌介导的转化破坏了一个编码具有肌球蛋白样马达结构域的几丁质合成酶的基因（BcchsV）。由此产生的突变体在生长特性或对番茄叶片的致病性方面没有明显差异。令人惊讶的是，与野生型菌株相比，BcchsV 突变体的几丁质含量增加了 31%（m/m）。此外，BcchsV 突变体对 Calcofluor White 的敏感性增加，对细胞壁破坏物质和渗透压调节剂（包括 SDS、山梨醇和 NaCl）的耐受性略有增强。这些结果表明，Bcchs 在 B. cinerea 细胞壁几丁质的合成中不起关键作用。然而，该基因的破坏引发了一种细胞对细胞壁损伤的反应的补偿机制。
