Separation and purification of proteinases from Gastric Mucosa of Northern Sheatfish,Silurus soldatovi

LIU Wei^1,2, ZHANG Xiu-mei², ZHAN Pei-rong¹, ZHANG Zhao-han³

1.Heilongjiang River Fisheries Research Institute,Chinese Academy of Fishery Sciences,Harbin 150070,China;2.College of Life Science and Technology,Ocean University of China,Qingdao 266003,China;3.State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,Harbin 150090,China



Abstract:

The separation and purification method for pepsin of Northern Sheatfish (Silurus soldatovi) was established by using the combination technology of salting-out,gel chromatography and gel electrophoresis,and the enzymic properties were also analyzed.The experimental results indicated that 28% and 56% (NH4)2SO4 saturation could separate the activated protease from the pepsin extract of gastric mucosa of Sheatfish (Silurus soldatovi) ;compared with the homogenate extraction,the pepsin specific activity of purified extraction by Sephadex G—75 gel chromatography system increased 598 fold,was 5 times higher than that of activated liquid,and the total production rate was 10.1%.The purified pepsin liquor at the conditions of pH3.3 0.01 M alanine-formic acid buffering solution,60 cm chromatography column,and the flowing rate of 0.8 ML/min was analyzed by SDS-PAGE,which indicated that there were two bands and the molecular weight was 34.0 kDa and 40.4 kDa,respectively.There were two peaks in the enzyme activity determination of the separated collecting liquor in gel chromatography,and the SDS-PAGE showed the concentrations of the two proteins was different,which indicated that it existed at least two pepsins in the gastric mucosa of Sheatfish (Silurus soldatovi).

Key words:  Sheatfish (Silurus soldatovi)  pepsin  separation and purification  property

DOI：10.11916/j.issn.1005-9113.2011.03.012

Clc Number:Q814

Fund: