[Interaction of perch fucolectin with Lewis antigens]

Interaction of fucolectin of perch Perca fluviatilis (PFL) with a set of Lewis antigens was studied by monitoring changes in its tryptophan fluorescence. PFL bound Le(c) (H type 1)-pentasaccharide (Ka = 6.6 x 10(3) M(-1)) and H type 6-trisaccharide (Ka = 2.5 x 10(3) M(-1)); essentially weaker, with Le(b)-hexasaccharide (Ka = = 4.0 x 10(2) M(-1)); and failed to interact with Le(a)-, Le(x)-, and Le(d)-containing oligosaccharides. PFL belongs to a new type of the fucolectins recognizing H-disaccharide Fuc alpha1-2Gal within various antigens, including H type 1/2 and Le(b).