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.
Solanum tuberosum Lectin (STA/STL) is conjugated to ferritin, that has a molecular weight of 474,000 g/mol (all 24 subunits combined). Ferritin-conjugated lectins can be used to visualize localization of specific saccharide moieties and examine the distribution of plasma membrane glycoproteins. These conjugates can be viewed via electron microscopy.