Recently a COVID-19 pneumonia pandemic caused by a novel coronavirus 2019-nCoV has broken out over the world. In order to better control the spread of the pandemic, there’s an urgent need to extensively study the virus’ origin and the mechanisms for its infectivity and pathogenicity. Spike protein is a special structural protein on the surface of coronavirus. It contains important information about the evolution of the virus and plays critical roles in the processes of cellular recognition and entry. In the past decades, spike protein has always been one of the most important objects in research works on coronaviruses closely related to human life. In this review we introduce these research works related to spike proteins, hoping it will provide reasonable ideas for the control of the current pandemic, as well as for the diagnosis and treatment of COVID-19.
Amyloid fibrils belong to a category of abnormal aggregations of natural proteins, which are closely related to many human diseases. Recently, some critical peptide sequences have been extensively studied for clarifying the molecular mechanism of natural proteins to form amyloid fibrils. In the present study, we designed a short peptide GGAAVV (GAV-6) composed of hydrophobic amino acids glycine (G), alanine (A) and valine (V) and studied its ability to form amyloid fibrils. As characterized by atomic force microscopy (AFM) and dynamic light scattering (DLS), the peptide could self-assemble into smooth nanofibers without branches. Congo red staining/binding and thioflavin-T (ThT) binding experiments show that the nanofibers formed by GAV-6 shared identical properties with typical amyloid fibrils. These results show that the designed peptide GAV-6 could self-assemble into typical amyloid fibrils, which might make it a useful model molecule to clarify the mechanism for the formation of amyloid fibrils in the future.