Abstract:Transglutaminase (TGase) from silver carp was purified with ammonium sulfate precipitation,gel filtration on Sephacryl S-300 high resolution and DEAE-Sepharose fast flow ion-exchange chromatography. Some kinetic properties of transglutaminase purified were studied. The results showed that the molecular mass of the purified enzyme was 100 ku. The enzyme exhibited final purification fold of 34.2,specific activity of 126.7 U/mg. Results of further assaying enzymatic characterization showed that the purified enzyme had maximal activity at 30℃ and pH 7.5. The activity of transglutaminase was slightly activated by Ca2+ and dithiothreitol (DTT) and strongly inhibited by ethylenediaminetetraacetic acid (EDTA). The metal ions Mg2+,Cu2+,Zn2+,Ba2+,Sn2+,Fe3+ strongly inhibited transglutaminase activity as well. The transglutaminase can catalyze covalent cross-linking of mysion heavy chain (MHC) from silver carp and grass carp. The effects of the transglutaminase on mysion from silver carp were more noticeable than that from grass carp.