Nucleic acids encoding -1,3 fucosyltransferases and expression systems for making and expressing them

The present invention relates generally to the field of 1,3-fucosyltransferases and, more specifically, to 1,3-fucosyltransferase polypeptides which are transmembrane segment-free. A bacterial 1,3-fucosyltransferase gene and deduced amino acid sequence is provided. The gene is useful for preparing 1,3-fucosyltransferase polypeptide, and active fragment thereof, which can be used in the production of oligosaccharides such as Lewis X, Lewis Y, and siayl Lewis X, which are structurally similar to certain tumor-associated carbohydrate antigens found in mammals. These product glycoconjugates also have research and diagnostic utility in the development of assays to detect mammalian tumors. In addition the polypeptide of the invention can be used to develop diagnostic and research assays to determine the presence of in human specimens.