An alkaline protease from Bacillus cereus NJSZ-13 can act as a pathogenicity factor in infection of pinewood nematode

[摘要] Endophytic bacteria are an important biological control for nematodes. We isolated the nematicidal Bacillus cereus NJSZ-13 from healthy Pinus elliottii trunks. Bioassay experiments showed killing of all tested nematodes by proteins from the NJSZ-13 culture filtrate within 72 h. Degradation of the nematode cuticles was observed, suggesting the action of extracellular bacterial enzymes. The responsible protease was purified by ammonium sulfate precipitation, hydrophobic interaction chromatography, ion-exchange chromatography, and SDS-PAGE. The protease had a molecular weight of 28 kDa and optimal activity at 55 °C and pH 9, indicating an alkaline protease. The study suggests the potential for using this B. cereus NJSZ-13 strain protease to prevent pinewood nematode infection.

[学科分类] 放射科、核医学、医学影像

[关键词] Endophytic bacteria;Bursaphelenchus xylophilus;Extracellular protease;Nematicidal activity;Bacillus cereus