Characterization of a D- galactose-binding lectin from seeds of Erythrina lysistemon

Emadeldin H. E Konozy

Biotechnology Park, Africa City of Technology, Khartoum, Sudan

Email: ehkonozy@yahoo.com; Tel: +249(0)999-104-999

Accepted 21 June, 2012

Abstract

A lectin from the seeds of Erythrina lysistemon (ElysL) was purified and characterized.  Purification strategy involved two different methodologies, which both resulted in a homogenous preparation. Native as well as subunit molecular weight of lectin were determined using gel filtration, SDS-PAGE and mass spectrometry. The glycoprotein nature of the lectin was judged by phenol-sulphuric acid test as well as by studying lectin interaction with Concanavalin A (ConA).  Hemagglutination ability of lectin was examined using various trypsin treated or untreated human and animal blood cells. Information about the lectin carbohydrate fine specificities was judged by hapten inhibition. Stability of lectin at different temperatures, pHs was explored. The secondary as well as tertiary structures of lectin were followed by Circular dichroism (CD) examination. Other physicochemical parameters like effect of metal ions; EDTA on lectin activity, isoelectric point, extinction coefficient etc were also done. Though the protein structurally looks like other lectins from the genus Erythrina, it seems markedly different in its biological interactions with receptors carbohydrates.

Keywords: leguminasae; Erythrina lysistemon lectin, D-galactose; purification; characterization