Affinity purified Solanum tuberosum lectin/agglutinin (STA/STL) is a hydroxyproline-rich glycoprotein. This lectin contains 50% carbohydrates, predominantly arabinose; and consists of two subunits. STA/STL binds oligomers of N-acetylglucosamine and some bacterial cell wall oligosaccharides containing N-acetylglucosamine and N-acetylmuramic acid. N-acetyllactosamine is a relatively weak inhibitor of hemagglutination induced by this lectin; though, it does not have a blood group specificity. Solanum tuberosum lectin has been shown to bind two and a half times more to colon cancer cells than normal tissue.
Texas Red is a red-fluorescent dye and when bound to Solanum tuberosum Lectin (STA/STL) can show the binding pattern of this lectin in cellular imaging applications. There is very little overlap between the emission spectra of Texas Red and FITC making this combination ideal for dual-labeling experiments. Rhodamine dyes, such as Texas Red, are more photostable and less sensitive to pH change when compared to other dyes such as fluorescein.