A monomeric mannose-binding lectin from inner shoots of the edible chive (Allium tuberosum)

A mannose-binding lectin was isolated from the inner shoots of the chive Al lium tuberosum. The procedure involved aqueous extraction, (NH4)(2)SO4 prec ipitation, dialysis to remove (NH4)2SO4, affinity chromatography on mannose -agarose, ion exchange chromatography on SP-Sepharose, gel filtration on Su perdex 75, and ion exchange chromatography on Mono S. Lectin activity was a dsorbed on mannose-agarose, SP-Sepharose, and Mono S. The lectin demonstrat ed a molecular weight of 13 kDa in sodium dodecyl sulfate-polyacrylamide ge l electrophoresis and gel filtration, indicating that it is a single-chain protein. N-terminal sequence analysis revealed its remarkable homology to A llium cepa lectin and similarity to a lesser extent to lectins from members of the Amaryllidaceae, Orchidaceae, and Liliaceae. The lectin manifested m itogenic activity in murine splenocytes and inhibitory activity against hum an immunodeficiency virus type 1 reverse transcriptase.