Detection of the mycovirus OMSV in the edible mushroom, Pleurotus ostreatus, using an SPR biosensor chip

Abstract

A surface plasmon resonance (SPR) biosensor chip was developed for the rapid detection of the oyster mushroom spherical virus (OMSV), which causes a mushroom die-back disease, the symptoms of which include malformed fruiting bodies and retarded mycelial growth in the cultivated edible mushroom, Pleurotus ostreatus. An anti-OMSV monoclonal antibody (mAb) was generated initially using purified OMSV viral particles. For the fabrication of the biosensor chip, the anti-OMSV mAb was layered onto an activated carboxymethyl-dextran (CM-Dex) gold thin film. Analysis on the SPR angle shift showed that the bound mAb was 6.7 ng/mm2 of the chip surface. Subsequently, the biosensor chip was applied to the detection of OMSV in the mushroom mycelial extract. It detected specifically OMSV in the extract in a concentration-dependent manner. Finally, the biosensor chip was employed for the detection of OMSV in the mushroom fruiting bodies collected from 10 commercial farms. Among the tested samples, OMSV was found to infect fruiting bodies from a farmland, and this was confirmed further via immunoblot analysis and a TAS-ELISA assay. In conclusion, the SPR biosensor chip combined with an anti-OMSV mAb evidenced superior performance, particularly with regard to the prompt detection of OMSV infection.