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.
The histidine box (HXXHH) is indicated with a black rectangular outline. Highly conserved aa residues (K, E, DT, L, HH, N, H, MY, YY, T, LF, F) are designated with the symbol ★.
