Barrasa J M, Gutiérrez A, Escaso V, Guillén F, Martínez M J, Martínez A T
Departamento de Biología Vegetal, Universidad de Alcalá, Madrid, Spain.
Appl Environ Microbiol. 1998 Jan;64(1):325-32. doi: 10.1128/AEM.64.1.325-332.1998.
The ligninolytic fungus Pleurotus eryngii grown in liquid medium secreted extracellular polysaccharide (87% glucose) and the H2O2-producing enzyme aryl-alcohol oxidase (AAO). The production of both was stimulated by wheat-straw. Polyclonal antibodies against purified AAO were obtained, and a complex of glucanase and colloidal gold was prepared. With these tools, the localization of AAO and extracellular glucan in mycelium from liquid medium and straw degraded under solid-state fermentation conditions was investigated by transmission electron microscopy (TEM) and fluorescence microscopy. These studies revealed that P. eryngii produces a hyphal sheath consisting of a thin glucan layer. This sheath appeared to be involved in both mycelial adhesion to the straw cell wall during degradation and AAO immobilization on hyphal surfaces, with the latter evidenced by double labelling. AAO distribution during differential degradation of straw tissues was observed by immunofluorescence microscopy. Finally, TEM immunogold studies confirmed that AAO penetrates the plant cell wall during P. eryngii degradation of wheat straw.
在液体培养基中生长的木质素分解真菌杏鲍菇分泌胞外多糖（87%为葡萄糖）和产过氧化氢的芳醇氧化酶（AAO）。两者的产生均受到麦秸的刺激。获得了针对纯化AAO的多克隆抗体，并制备了葡聚糖酶与胶体金的复合物。利用这些工具，通过透射电子显微镜（TEM）和荧光显微镜研究了在固态发酵条件下液体培养基和秸秆中降解的菌丝体中AAO和胞外葡聚糖的定位。这些研究表明，杏鲍菇产生由薄葡聚糖层组成的菌丝鞘。该鞘似乎在降解过程中参与菌丝体与秸秆细胞壁的粘附以及AAO固定在菌丝表面，后者通过双重标记得以证明。通过免疫荧光显微镜观察了秸秆组织差异降解过程中AAO的分布。最后，TEM免疫金研究证实，在杏鲍菇降解小麦秸秆过程中，AAO穿透植物细胞壁。
