PURPOSE: To isolate transglutaminase for catalyzing an acyl rearrangement reaction of a γ-carboxamide group of glutamine residue in a peptide chain derived from a fascia material of Halocynthia roretzi.

CONSTITUTION: A fascia material after removal of perisarc of Halocynthia roretzi is added to a buffer solution (pH7.0), ground by a homogenizer, the ground solution is centrifuged, the supernatant liquid is collected to give a crude extracted solution of transglutaminase. The extracted solution is dialyzed with a buffer solution, passed through a column packed with an anion exchange resin, the column is cleaned with a buffer solution and the adsorbed material is eluted with 0-500mM KCl solution having a concentration gradient. Then the eluate is passed through a hydrophobic column in 35% ammonium sulfate saturated buffer solution and the adsorbed material is eluted with a concentration gradient solution of ammonium sulfate having 35-0% degree of saturation. Successively, the eluate is purified by affinity chromatography comprising cadaverine as a ligand to give transglutaminase. The enzyme can gelatinize ≥1.0% protein-containing solution or slurry.