FN1 and colorectal carcinoma: To test this, we chose Fn clinical tumor isolate (CTI)-2 because CTI-2 expresses a membrane protein, Fap2, that mediates the adhesion of Fn to colon cancer cells overexpressing Gal-GalNAc to promote the development of CRC.45 Additionally, we also found that the protein sequences for PtaT are identical between CTI-2 and Fn ATCC 23726.