Abstract
A skin mucus extract of the loach Misgurnus anguillicaudatus agglutinated various types of mammalian erythrocytes including rabbit, sheep, human A, B, and AB. It did not react with horse or human 0 erythrocytes. The hemagglutinating activity of the mucus extract was lost when heatedand also at extreme pHs. The activitywas independent of the presence of calcium ion. Crossed absorptiontests revealedthat the skin mucus extract contained a single type of non-blood group specific lectins. Askin mucus lectin, named MAL-1, was isolated by ion-exchange column chromatography followed byrepeated gel-filtration on Sepharose S-200. The molecular weight of the intact MAL-1 was greater than300 kDa and consisted of heterogeneous subunits (40 and 41 kDa). MAL-1 was a glycoprotein and contained D-galactose(13.6%), D-mannose (2.1%), and L-xylose (2.5%). The absence of Cys residue in MAL-1 suggested that MAL-1 molecule held non-covalently. MAL-1 reacted with antibodies for the conger eel mucus lectin but not with those for acorn barnacle lectins. The lectin (MAL-2) having a smaller molecular weight was also present in themucus extract.
