Porcine epidemic diarrhea virus (PEDV) belongs to the alphacoronavirus family. PEDV is highly contagious and particularly lethal for infected piglets. Despite its apparent threat to the pork industry, Taiwan has no effective vaccination program. The research team led by Dr. Shang-Te Danny Hsu at the Institute of Biological Chemistry, Academia Sinica, in collaboration with Dr. Kay-Hooi Khoo at the same institute, and Prof. Hui-Wen Chang at the School of Veterinary, National Taiwan University, integrated cryo-electron tomography (cryo-ET), cryo-electron microscopy (cryo-EM), mass spectrometry (MS), and protein engineering to reveal the dynamic nature of the spike protein of a highly infectious strain of PEDV identified in Pingtung (PT52). This work has been published online in Nature Communications in August, 2022 (https://doi.org/10.1038/s41467-022-32588-3).
This is the first cryo-ET report from Taiwan that demonstrated the ability to determine atomic structures of biomacromolecules – in this case, the spike proteins as part of intact viral particles. The research team also established a recombinant protein production platform based on a porcine cell line to enable detailed MS analysis of the glycosylation profile of the PEDV spike protein produced by its native host cells. The ability to produce and characterize the molecular details of recombinant PEDV spike proteins will help PEDV vaccine development and disease control in the future.