Main Page

by David Canner
The X-ray structure of HIV-1 protease reveals that it is composed of two symmetrically related subunits which form a tunnel where they meet. This is critical because it contains the active site of the protease, consisting on two Asp-Thr-Gly conserved sequences, making it a member of the aspartyl protease family. The two catalytic Asp's either interact with the incoming water or protonate the carbonyl to make the carbon more electrophilic for the incoming water.

>>> Visit this page >>>

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 >>>

The Capsid of a virus is its outer shell or "skin". Viruses have evolved intricate and elegant ways to assemble capsid protein chains into complete, usually spherical capsids, often with icosahedral symmetry. Pictured is an extremely simplified model of a capsid, where a single enlarged atom represents each of the 360 protein chains in the capsid of the Simian Virus 40 (SV40), a member of a group of cancer-causing viruses that has been extensively researched for decades.

>>> See more animations and explanation >>>