Affinity purified Lotus tetragonolobus lectin (LTL) is isolated from lotus seeds and is composed of 240 amino acid residues. LTL is a glycoprotein consists of four subunits. This lectin has different isoelectric points of pH 7.3, 7.6, 7.9, 8.2 and a carbohydrate specificity toward α-fucose, it is most inhibited by L-fucose. LTL is a fucose-binding anti-H(O) lectin. Transitional cell carcinoma of the human urinary bladder tends to metastasize when it strongly expresses binding sites for LTL.
Cy5, when bound to Lotus tetragonolobus Lectin (LTL), can show the binding pattern of this lectin in cellular imaging and flow cytometry. The excitation wavelength required for Cy5 to fluoresce is high enough to avoid overlap with most other fluorochromes, making it useful for dual-labeling experiments. Because of this high excitation, there is typically less background from autofluorescence of biological specimens.