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.
Chemical structure of PQQ. All of the carbons and nitrogens in PQQ come from a glutamate and tyrosine in an absolutely conserved EXXXY sequence located in the precursor peptide, PqqA. Atoms and bonds in red are derived from the glutamate, and those in blue are from the tyrosine. Black represents modifications during biosynthesis.
