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.
Quantitation of proteins by their tryptic peptide fragments. A tryptic peptide fragment FTGWYDVDLSEK (MW 1459.81) from S. Enteritidis phosphoglyceromutase was analyzed for the level of downregulation. A peak at m/z 1473 represents 15N-labeled population (upper spectrum), which does not appear in the unlabeled population. The ratio of two peak intensities (27 and 17, respectively) represents a relative protein expression level of 0.6, or a 40% downregulation.
