Hao Tianyi, Chen Sanfeng
State Key Laboratory of Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing, P. R. China.
PLoS One. 2017 Jan 11;12(1):e0169980. doi: 10.1371/journal.pone.0169980. eCollection 2017.
Paenibacillus polymyxa WLY78 is a nitrogen fixer and it can be potentially applied to biofertilizer in agriculture. In this study, P. polymyxa WLY78 is labelled with gfp gene. The GFP-labelled P. polymyxa WLY78 is used to inoculate wheat, maize and cucumber seedlings grown in the gnotobiotic system and in soil, respectively. Observation by confocal laser scanning microscope reveals that the GFP-labeled bacterial cells are mainly located on the root surface and epidermis of wheat, and only a few cells are present within cortical cells. In maize and cucumber seedlings, bacterial cells were colonized in epidermal and cortical cells, intercellular spaces and vascular system of root, stem and leaf tissue interiors besides on root surfaces. Higher densities of the bacterial cells in roots, stems and leaves indicated that P. polymyxa WLY78 cells could migrate from roots to stems and leaves of maize and cucumber. This study will provide insight into interaction between P. polymyxa WLY78 and host cells.
多粘芽孢杆菌WLY78是一种固氮菌，具有潜在的农业生物肥料应用价值。在本研究中，多粘芽孢杆菌WLY78用绿色荧光蛋白（gfp）基因进行标记。分别用绿色荧光蛋白标记的多粘芽孢杆菌WLY78接种在无菌培养系统和土壤中生长的小麦、玉米和黄瓜幼苗。通过共聚焦激光扫描显微镜观察发现，绿色荧光蛋白标记的细菌细胞主要位于小麦根表面和表皮，皮层细胞内仅有少数细胞。在玉米和黄瓜幼苗中，细菌细胞除了在根表面定殖外，还在根、茎、叶组织内部的表皮和皮层细胞、细胞间隙和维管系统中定殖。根、茎、叶中细菌细胞密度较高，表明多粘芽孢杆菌WLY78细胞可从玉米和黄瓜的根迁移到茎和叶。本研究将为深入了解多粘芽孢杆菌WLY78与宿主细胞之间的相互作用提供依据。
