IMMUNOELECTRON MICROSCOPIC STUDY OF THE POROSITY OF BROWN-ROT DEGRADED PINE WOOD

Pine wood (Pinus sylvestris) degraded by the brown-rot basidiomycete Fomitopsis pinicola was infiltrated with ovalbumin (45,000 D) and myoglobin (16,500 D). The penetrability of the degraded cell walls by these marker proteins was investigated by immunoelectron microscopy. It was found that even at 70% weight loss ovalbumin did not penetrate the cell walls. With myoglobin both no penetration and full penetration was observed. The different behavior of the two proteins was proved by double labeling. The results strongly suggest that not only the initial cellulose depolymerization as believed so far but also the solubilization of polysaccharides and lignin modification during brown-rot decay is caused by a low molecular weight agent. The validity of the immunogold labeling method to demonstrate antigens within wood cell walls was proved by double labeling.