Recombinant protein expression of Moringa oleifera lectin in methylotrophic yeast as active coagulant for sustainable high turbid water treatment.

Muhamad Azhar Abd Wahid,Hirofumi Hara,Nor’Azizi Othman,Ahmad Jusoh,Zuriati Zakaria,Thamer Ahmad Mohammed,Masafumi Goto,Norio Sugiura,Megat Johari Megat Mohd Noor

doi:10.1080/09168451.2017.1329617

Abstract

The natural coagulant Moringa oleifera lectin (MoL) as cationic protein is a promising candidate in coagulation process of water treatment plant. Introducing the gene encoding MoL into a host, Pichia pastoris, to secrete soluble recombinant protein is assessed in this study. Initial screening using PCR confirmed the insertion of MoL gene, and SDS-PAGE analysis detected the MoL protein at 8kDa. Cultured optimization showed the highest MoL protein at 520mg/L was observed at 28°C for 144h of culturing by induction in 1% methanol. Approximately, 0.40mg/mL of recombinant MoL protein showed 95±2% turbidity removal of 1% kaolin suspension. In 0.1% kaolin suspension, the concentration of MoL at 10μg/mL exhibits the highest turbidity reduction at 68±1%. Thus, recombinant MoL protein from P. pastoris is an effective coagulant for water treatment.

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