Chinese scientists see the giant African swine fever virus clearly for the first time
Since the first case of African swine fever occurred in August last year, China's hog farming market has been greatly impacted. This year, the scale of hog farming in many regions has been substantially reduced, causing pork prices to rise. Recently, research teams from the Chinese Academy of Sciences and the Chinese Academy of Agricultural Sciences analyzed the molecular structure of the swine virus prevalent in China, which has had an important impact on the prevention and control of the swine fever virus. The following article comes from Tencent.
China is a major producer and consumer of hogs, with hog production accounting for about half of the global total. But “African swine fever” is a nightmare for many farmers. Since the Information Office of the Ministry of Agriculture and Rural Affairs reported China's first outbreak on August 3 last year, it has caused more than 100 billion yuan in economic losses.
On October 18, good news arrived. The Chinese Academy of Sciences and the Chinese Academy of Agricultural Sciences announced that Chinese scientists had, for the first time, analyzed the fine three-dimensional structure of the African swine fever virus particle that is plaguing countries around the world. This achievement will have an important impact on advancing the prevention and control of African swine fever.
In the early hours of October 18, the joint research team's paper on the “structure and assembly mechanism of African swine fever virus” was published in the international academic journal Science.
The African swine fever virus is a “big guy”
China experienced its first African swine fever outbreak in August 2018. This was the first time the African swine fever virus had entered China since it was discovered in Kenya in 1921. The outbreak has severely affected the hog farming industry and pork prices, causing losses of more than 100 billion yuan.
After the African swine fever outbreak in China, the team of Rao Zihe and Wang Xiangxi at the Institute of Biophysics of the Chinese Academy of Sciences and the team of Bu Zhigao at the Harbin Veterinary Research Institute of the Chinese Academy of Agricultural Sciences, together with ShanghaiTech University, Tsinghua University, the Institute of Microbiology of the Chinese Academy of Sciences, the Wuhan Institute of Virology, Nankai University and other institutions, began in December 2018 to carry out joint research on basic science, clinical testing and highly effective vaccines involving African swine fever virus particles and related antigen molecules.
According to the research team, African swine fever is a worldwide problem. The scientific community does not clearly understand what the life cycle of this virus is, nor the immune mechanisms it triggers in the body. It is not even clear how many proteins it has, much less how it invades and how it replicates.
This time, they successfully isolated the prevalent strain of African swine fever virus behind the ongoing outbreak in China. They found that the African swine fever virus is “enormous in scale.”
Since 2013, the research team has analyzed the atomic-resolution structures of more than 30 whole viruses of 4 types. From structural comparisons, it can be seen that the African swine fever virus is an extremely large and complex pathogen.
Among the atomic-resolution structures of more than 30 whole viruses of 4 types analyzed by the team since 2013, the African swine fever virus is an extremely large and complex pathogen. This brought enormous challenges for data collection. The research team carried out four consecutive months of massive data collection.
In the end, they used the single-particle three-dimensional reconstruction method to analyze for the first time the three-dimensional structure of the whole African swine fever virus particle, clarifying the unique 5-layer structural features of the African swine fever virus. The virus particle contains more than 30,000 protein subunits, assembled into a spherical particle with a diameter of about 260 nanometers, making it the largest virus particle for which a near-atomic-resolution structure has been analyzed to date.
Cross-sectional diagram of the overall 5-layer structure of the African swine fever virus
Overall structure of the capsid layer of the African swine fever virus
Feng Zhongwu, vice president of the Chinese Academy of Agricultural Sciences, said that since the beginning of this year, hog production has declined sharply compared with last year, and this research is “responding to the country's needs and addressing the country's urgent concerns.”
>>Recommended reading: What is the three-dimensional structure of African swine fever? How is the related vaccine progressing?