Identification, Characteristics and Mechanism of 1-Deoxy-N-acetylglucosamine from Deep-Sea Virgibacillus dokdonensis MCCC 1A00493
作者:Dian Huang、Zong-Ze Shao、Yi Yu、Min-Min Cai、Long-Yu Zheng、Guang-Yu Li、Zi-Niu Yu、Xian-Feng Yi、Ji-Bin Zhang、Fu-Hua Hao
DOI:10.3390/md16020052
日期:——
Xanthomonas oryzae pv. oryzae, which causes rice bacterial blight, is one of the most destructive pathogenic bacteria. Biological control against plant pathogens has recently received increasing interest. 1-Deoxy-N-acetylglucosamine (1-DGlcNAc) was extracted from the supernatant of Virgibacillus dokdonensis MCCC 1A00493 fermentation through antibacterial bioassay-guided isolation. Its structure was elucidated by LC/MS, NMR, chemical synthesis and time-dependent density functional theory (TD-DFT) calculations. 1-DGlcNAc specifically suppressed X. oryzae pv. oryzae PXO99A (MIC was 23.90 μg/mL), but not other common pathogens including Xanthomonas campestris pv. campestris str.8004 and Xanthomonas oryzae pv. oryzicola RS105. However, its diastereomer (2-acetamido-1,5-anhydro-2-deoxy-d-mannitol) also has no activity to X. oryzae pv. oryzae. This result suggested that activity of 1-DGlcNAc was related to the difference in the spatial conformation of the 2-acetamido moiety, which might be attributed to their different interactions with a receptor. Eighty-four unique proteins were found in X. oryzae pv. oryzae PXO99A compared with the genome of strains8004 and RS105 by blastp. There may be unique interactions between 1-DGlcNAc and one or more of these unique proteins in X. oryzae pv. oryzae. Quantitative real-time PCR and the pharmMapper server indicated that proteins involved in cell division could be the targets in PXO99A. This research suggested that specificity of active substance was based on the active group and spatial conformation selection, and these unique proteins could help to reveal the specific mechanism of action of 1-DGlcNAc against PXO99A.
引起稻米细菌性斑点病的黄单胞菌(Xanthomonas oryzae pv. oryzae)是最具破坏性的病原菌之一。近年来,针对植物病原菌的生物防治受到了越来越多的关注。1-脱氧-N-乙酰氨基葡萄糖(1-DGlcNAc)是从维尔吉巴克氏菌(Virgibacillus dokdonensis)MCCC 1A00493发酵的上清液中通过抗菌生物活性导向分离提取得到的。其结构通过液相色谱-质谱联用(LC/MS)、核磁共振(NMR)、化学合成和时间相关密度泛函理论(TD-DFT)计算进行了阐明。1-DGlcNAc能够特异性抑制X. oryzae pv. oryzae PXO99A(最低抑制浓度为23.90 μg/mL),但对其他常见病原菌如黄单胞菌(Xanthomonas campestris pv. campestris str.8004)及稻瘟病菌(Xanthomonas oryzae pv. oryzicola RS105)无活性。然而,其一个二旋映体(2-乙酰氨基-1,5-脱水-D-甘露醇)同样对X. oryzae pv. oryzae没有活性。这个结果表明,1-DGlcNAc的活性与2-乙酰氨基基团的空间构象差异有关,这可能归因于它们与受体的不同相互作用。通过blastp分析,发现与8004和RS105菌株基因组相比,X. oryzae pv. oryzae PXO99A中有84种独特蛋白存在。这些独特蛋白可能与1-DGlcNAc之间存在独特的相互作用。定量实时PCR和pharmMapper服务器显示,与细胞分裂相关的蛋白可能是PXO99A中的靶点。本研究表明,活性物质的特异性基于活性基团和空间构象的选择,这些独特蛋白可能有助于揭示1-DGlcNAc对PXO99A的特定作用机制。