Coomassie brilliant blue stained acrylamide/bisacrylamide gel showing purification of CELTN at 25°C. Lane L, protein ladder (The Precision Plus, Bio-Rad, USA); Lane 1, the BL21 CodonPlus (DE3) total cells having pET-CEL collected after 22h of induction with final concentration of 0.5 mM IPTG at 25°C; Lane 2, insoluble part after lysis of cells in Lane 1; Lane 3, soluble part after lysis of cells in Lane 1; Lane 4, purified CELTN after Ni-NTA affinity column chromatography.