▎ 摘　　要

NOVELTY - Method for separating and purifying a fusion protein glucosidase (Glu)-linker-elastin-like polypeptide (ELP)-graphene-binding (GB) (GLEGB), involves (i) linking the ELP amino acid sequence and the GB polypeptide to Glu using a linker, constructing the recombinant plasmid pET-GLEGB, and transforming the recombinant plasmid into a host cell to express the fusion protein, (ii) mixing the bacterial solution containing fusion protein, a surfactant and ammonium sulfate as a lower phase, and polyethylene glycol 2000 (PEG2000) as an upper phase, carrying out floatation, collecting an upper phase solution and lower phase solution after flotation, recording the volume, and measuring the enzyme activity and protein content in the upper phase and lower phase after flotation, (iii) adding ammonium sulfate to the collected supernatant, heating in a water bath, centrifuging to remove supernatant, and carrying out suspension precipitation, incubating and centrifuging. USE - Method for separating and purifying fusion protein GLEGB. ADVANTAGE - The method is simple, economical and environmentally-friendly, and improves the purification efficiency. DETAILED DESCRIPTION - Method for separating and purifying a fusion protein glucosidase (Glu)-linker-elastin-like polypeptide (ELP)-graphene-binding (GB) (GLEGB), involves (i) carrying out induced expression of fusion protein GLEGB by linking the ELP amino acid sequence and the GB polypeptide to Glu using a linker, constructing the recombinant plasmid pET-GLEGB, and transforming the recombinant plasmid into a host cell to express the fusion protein, (ii) mixing the bacterial solution containing fusion protein, a surfactant and ammonium sulfate as a lower phase, and polyethylene glycol 2000 (PEG-2000) as an upper phase, carrying out floatation, collecting an upper phase solution and lower phase solution after flotation, recording the volume, and measuring the enzyme activity and protein content in the upper phase and lower phase after flotation, (iii) adding ammonium sulfate to the collected supernatant, heating in a water bath, centrifuging to remove supernatant, and carrying out suspension precipitation using Tris-HCl buffer solution, incubating for certain time at low temperature, and centrifuging to remove impurities to obtain a purified target enzyme solution.