Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Protofilaments shown through the XY-plane, perpendicular to the helical axis. β-strands correspond to coloured, arrowed bars. Red arrowheads point to internal densities. Fuzzy densities on the outside of protofilaments are not shown.
