Ferket Kathelijne K A, Levery Steven B, Park Chaeho, Cammue Bruno P A, Thevissen Karin
Centre of Microbial and Plant Genetics, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Heverlee, Belgium.
Fungal Genet Biol. 2003 Nov;40(2):176-85. doi: 10.1016/s1087-1845(03)00085-9.
Twenty-five Neurospora crassa mutants obtained by chemical mutagenesis were screened for increased resistance to various antifungal plant defensins. Plant defensin-resistant N. crassa mutants were further tested for their cross-resistance towards other families of structurally different antimicrobial peptides. Two N. crassa mutants, termed MUT16 and MUT24, displaying resistance towards all plant defensins tested but not to structurally different antimicrobial peptides were selected for further characterization. MUT16 and MUT24 were more resistant towards plant defensin-induced membrane permeabilization as compared to the N. crassa wild-type. Based on the previously demonstrated key role of fungal sphingolipids in the mechanism of growth inhibition by plant defensins, membrane sphingolipids of MUT16 and MUT24 were analysed. Membranes of these mutants contained structurally different glucosylceramides, novel glycosylinositolphosphorylceramides, and an altered level of steryl glucosides. Evidence is provided to link these clear differences in sphingolipid profiles of N. crassa mutants with their resistance towards different plant defensins.
对通过化学诱变获得的25个粗糙脉孢菌突变体进行筛选，以寻找对各种抗真菌植物防御素抗性增强的突变体。对具有植物防御素抗性的粗糙脉孢菌突变体进一步测试其对其他结构不同的抗菌肽家族的交叉抗性。选择了两个粗糙脉孢菌突变体，分别命名为MUT16和MUT24，它们对所有测试的植物防御素都有抗性，但对结构不同的抗菌肽没有抗性，以便进一步表征。与粗糙脉孢菌野生型相比，MUT16和MUT24对植物防御素诱导的膜通透性更具抗性。基于先前证明的真菌鞘脂在植物防御素生长抑制机制中的关键作用，对MUT16和MUT24的膜鞘脂进行了分析。这些突变体的膜含有结构不同的葡糖神经酰胺、新型糖基肌醇磷酸神经酰胺以及甾醇糖苷水平的改变。有证据表明粗糙脉孢菌突变体鞘脂谱的这些明显差异与其对不同植物防御素的抗性有关。
