Studies On Purification And Enzymological Characterazation Of Trypsin-like Enzyme From Euphausia Pacifica

Euphausia Pacifica which belongs to Arthropoda Crustacea, is the subarctic dominant species, distributing broadly in Far East sea area, Yellow Sea and Taiwan Strait hereabout.Trypsin-like Enzymes of krill have high bioactivity and performed well in use. And the study basic of Euphausia pacifica is substantial. But Euphausia Superba and its congener have being paid more attention on distribution and structure characterization. At present, the usage of krill is mostly limited at aquatic product feedstuff and additive. Correspondingly, no attention have been paid on its digestant enzymes and their functions. Accordingly the purification of Euphausia pacifica's trypsin-like enzyme and the enzyme kinetics study has significant theoretic and practical importance.Enzyme kinetics and application of trypsin-like enzymes were researched, and had some significant achievement. By 55⁶5% saturation of (NH4)2SO4 fractional precipitation, DEAE-Sepharose-Fast Flow ion-exchange chromatography, and then by Sephacryl S200 gel chromatography, Euphausia pacifica's trypsin-like enzyme TLEâ… is attained, which has a molecular weight of 31.0 kDa by SDS-PAGE with 12.5% separation gel. By 85% saturation (NH4)2SO4 fractional precipitation, and then by Benzamidine-Sepharose4B affinity chromatography, Euphausia pacifica's trypsin- like enzyme TLEâ…¡is attained, which has a molecular weight of 59.6kDa by SDS-PAGE with 12.5% separation gel.The study on the enzyme kinetics of TLEâ… with BApNA as substrate shows that, TLEâ… 's K_m=(0.177±0.0185)×10^-3 mol·L^-1, Vmax=(7.67±0.686)×10^-5 mol...