Revista de Bioprocessamento e Biotécnicas

Mass Spectrometric Characterization of a Novel Galactose- Binding Lectin from Chlorella sorokiniana (MW769776)

Abstract

Savitha J*, Roopashri N Arekal, Ashwini Kumar, Gunashree BS and Divyashree MS

A freshwater green microalgal strain was isolated, and presence of lectin was identified by its strong Hemagglutination Activity (HA). The molecular characterization of algal strain was found to be the Chlorella sorokiniana (MW769776). The Chlorella Sorokiniana Lectin (CSL) was purified by single-step affinity chromatography method using guar-gum as a resin. The precipitate showed single active peak with titer value of 1024 HU, specific activity of 539 mg/mL, and with purification factor. The purified lectin revealed single band on denaturing electrophoresis with. Liquid Chromatography-Electrospray Ionization-Quadrupole-Time of Flight Mass Spectrometry (LC-ESI-Q-TOF-MS) analysis of tryptic digested purified lectin suggested that it was a monomeric protein. A multiple sequence alignment study revealed that the peptide sequences of CSL exhibited similarity with the H-type lectin domain from Micractinium conductrix. The structure of CSL was studied by FTIR and homology modeling methods, indicating that its secondary structure contained α-helix, β-sheet, and unordered structure, whereas the 3D structure exhibited the similarity with proteins from light-harvesting reaction center complex of photosystem I. The main significance of this study includes the characteristics of CSL are consistent with its identification as a hemagglutinin, a kind of novel lectin, which suggests its candidature for various biological purposes.