Purification of bovine liver transglutaminase by gel filtration

Abstract

Transglutaminases (TGases) are enzymes that catalyze transfer of acyl group and covalent crosslinks formation between peptide-bound glutaminyl residues and amino groups. TGases have many industrial applications and have been purified from various sources. TGase was purified from the bovine liver extract by gel filtration on Sephacryl S-200 HR column. TGase activity was measured using CBZ-l-glutaminylglycine & hydroxylamine and the enzyme was characterized with respect to its response to different temperatures, pHs and salt concentrations. TGase was purified by yield 36.7%, had a weight 74 kDa, a high pH (pH = 8) and temperature (45 °C) optimum. The enzyme was observed to be stable at temperatures below 55 °C and was stable within a narrow pH range of 6.5–8.0. Purified TGase showed Ca2+ dependent characteristics and tended to retain activity at a high NaCl concentration. These results revealed that purified TGase can be used as a potential alternative to other sources.