Identification of human basic fetoprotein as glucose-6-phosphate isomerase by using N- and C-terminal sequence tags and terminal tag database.

Human basic fetoprotein (BFP), found in fetal serum and tissue extracts as well as in extracts of various cancer tissues, has long been known as a marker protein for cancers; however, the primary sequence has not yet been reported. This paper describes the identification of BFP using the N- and C-terminal amino acid sequence tags (Ac-AALTRDPQFQ and QQREARVQ, respectively) clarified by mass spectrometry-based methods, and a terminal tag database (ProteinCarta). In this study, BFP was identified as glucose-6-phosphate isomerase (G6PI_HUMAN).