Isolation and characterization of Dorin M, a lectin from plasma of the soft tick Ornithodoros moubata

A lectin with high hemagglutinating activity, which we have named Dorin M, was identified in the plasma of the soft tick Ornithodoros moubata. The act ivity of the plasma lectin could be efficiently inhibited by sialic acid, N -acetyl-D-hexosamines and sialoglycoproteins. Dorin hi was purified to homo geneity using two different isolation systems: affinity chromatography on a column of bovine submaxillary mucin conjugated to Sepharose 4B with specif ic elution by N-acetyl-D-glucosamine and chromatography on Blue-Sepharose f ollowed by anion exchange FPLC on a MonoQ column. The purified lectin is a glycoprotein which, in the native state, forms aggregates with molecular ma ss of about 640 kDa. Non-reducing SDS PAGE revealed that the lectin consist s of two noncovalently bound subunits migrating closely around 37 kDa. Dori n M is a glycoprotein, probably modified by N-type glycosylation. After che mical deglycosylation, only one band of about 32 kDa was detected. Dorin M is the first lectin purified from ticks. (C) 2000 Elsevier Science Ltd. All rights reserved.