Main Page

Coronavirus Spike Protein Priming

by Eric Martz
Coronavirus SARS-CoV-2 (responsible for COVID-19) has a spike protein on its surface, which enables it to infect host cells. Initially, proteases in the lungs clip the homo-trimeric spike protein at a unique sequence. This primes it, causing it to extend its receptor binding surface (shown in the above animation), optimizing binding to the host cell's ACE2 receptor (not shown). Next, spike protein initiates fusion of the virus and host cell membranes (not shown), enabling the virus RNA to enter the cell and initiate production of new virions. Knowledge of spike protein's molecular structure and function is crucial to developing effective therapies and vaccines.
>>> Visit this page >>>

Structural flexibility of the periplasmic protein, FlgA, regulates flagellar P-ring assembly in Salmonella enterica.

H Matsunami, YH Yoon, VA Meshcheryakov, K Namba, FA Samatey. Scientific Reports 2016 doi: 10.1038/srep27399
A periplasmic flagellar chaperone protein, FlgA, is required for P-ring assembly in bacterial flagella of taxa such as Salmonella enterica or Escherichia coli. Here we present the open and closed crystal structures of FlgA from Salmonella enterica serovar Typhimurium, grown under different crystallization conditions. An intramolecular disulfide cross-linked form of FlgA caused a dominant negative effect on motility of the wild-type strain.

>>> Visit this I3DC complement >>>

Eastern Equine Encephalitis virus
Although only a few people in the USA get Eastern Equine Encephalitis every year, the fatality rate is 30%, and many survivors have ongoing neurological problems. The virus is transmitted by mosquitoes from animals, especially birds, to humans. This RNA virus has a complicated capsid (a slab of which is shown) composed of protein shells with an enclosed lipid bilayer. The structures of virus capsids can be explored using free FirstGlance in Jmol.

>>> Visit I3DC Interactive Visualizations >>>