The mysteries of the coronavirus

In the past 20 years, the remaining three coronavirus gradually appeared in the animal hosts, and cause outbreaks in the global scope, lead to serious respiratory diseases and even many deaths.In 2002 the outbreak of severe acute respiratory syndrome (SARS) is by the SARS coronavirus (SARS - CoV);In 2012, the Middle East respiratory syndrome coronavirus (MERS - CoV) was found, and continuously lead to accidental and local epidemic outbreak.

Recently to human coronavirus infection is the severe acute respiratory syndrome coronavirus type 2 (SARS - CoV - 2), in December 2019, it was first reported in China, then in March 2020, the world health organization (WHO) has identified as a global pandemic.The virus causes disease called COVID - 2019, also is a kind of respiratory disease, can cause mild flu-like symptoms and even fatal lung disease.

The virus to infect a living organism, must invade the cells, and then reproduce and persistent infection to other hosts.Type of virus which cells will be affected, coronavirus main cells attack the respiratory system.With the outbreak of SARS and the MERS, and, more recently, the new crown pneumonia virus, researchers have been studying how the virus into our cells, and hope to find a method of prevention.

When coronary virus enters the body, they must and lipid membrane fusion of the host cell, and then you can pass their genetic material.At present we have not clear fusion mechanism, but is known, a structure is classified as type I virus fusion protein, and the influenza virus and HIV/AIDS in the same group of S protein, will drive the virus combination and invasion of cells.S protein protein shear revealed that it is the fusion peptide (FP) launched the membrane fusion.As an important part of coronavirus attack cells, localization and characterization of FP is the priority for the team, but it's exact location has been controversial.

The researchers used to locate coronavirus is a technique of FP electron paramagnetic resonance (EPR) spectrum.EPR can be used for identification and quantitative solid, liquid, gas, cells and the body of paramagnetic substance (free radicals and transition metal ions).Therefore, EPR is a common analysis method, applicable to from a series of application of nanometer diamond to the cell membrane.

A study using the technology of EPR (ELEXSYS, Bruker) of the SARS virus FP peptide lipid membrane interaction analysis of the structure and function.The study simulates the different from SARS coronavirus isolated peptides can be combined with the synthetic lipid membrane, namely multilayer film bubble (MLVs).Multilayer film bubble through a special, nitrogen oxides is called spin tag is marked, it is sensitive to the local environment.Using membrane sequence as parameters, can identify the FP from peptide mixture, because it can lead to the change of the EPR spectrum lines width, and the linear.Use EPR technology, the team can identify and characterize the FP of the SARS coronavirus.

SARS coronavirus was chosen as a model, because we have a lot of functional data are available.But the FP is widespread in the coronavirus family, so the research findings are applicable to all such viruses, including MERS and any new virus broke out in animal hosts, such as the new virus.Similar studies continue to deepen our understanding of how the coronavirus infection the body, and help to achieve the ultimate goal of to prevent the spread of the virus.

1. Lai, AL, Millet JK, Daniel S, Freed JH and Whittaker GR (2017) of The SARS - CoV Fusion Peptide Forms an Extended Bipartite Fusion Platform that Perturbs be Order in a Calcium - Dependent Manner, J Mol Biol, 8;429 (24) : 3875-3892.

Pictures from David s. Goodsell, Bank Protein Data Bank;Doi: 10.2210 / rcsb_pdb/goodsell - gallery - 019

Pictures depicting a just into the lungs of coronavirus, it was breathing cells secrete mucus, antibody and surrounded by a few small immune system proteins.Virus is surrounded by a layer of membrane, the membrane S protein contain catch echo it enter cells, the kernel protein involved in cell organization of M protein, as well as the cell membrane channel E protein, it involved in virus budding and possibly into virus particles in this process.The nucleoprotein including many combined with genomic RNA copies of N protein.