SEQUEST

SEQUEST is a computer program used by scientists to identify proteins in complex biological samples. It works by taking experimental mass spectrometry data—measurements of protein pieces called peptides—and comparing these to theoretical peptide patterns generated from known protein databases. By matching these patterns, SEQUEST determines which proteins are likely present in the sample. This process helps researchers understand the makeup of biological systems, such as how cells function or how diseases develop, by accurately pinpointing the proteins involved.