1.College of Food Science and Engineering,Dalian Ocean University,Dalian 116023,China;2.Alkali Soil Natural Environmental Science Center, Northeast Forestry University/Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field,Ministry of Education,Harbin 150040,China;3.College of Marine Science and Environment,Dalian Ocean University,Dalian 116023,China;4.College of Fisheries and Life Science, Dalian Ocean University,Dalian 116023,China
Abstract: A N-acetyl-D-galactosamine(GalNAc)-/mucin from porcine stomach(PSM)-specific lectin(MCL -T)was purified from Manila clamRuditapesphilippinarumusing a combination of ion exchange on Cellulose DE52 and gel filtration on Sephadex G-100 and HPLC on TSK-GEL G3000PWXL.Molecular weight of the MCL-T was determined by SDS-PAGE to be 148 000,containing two kinds of subunits,62 000 and 36 000.The MCL-Twas found to show the antibacterial activities againstStaphylococcusaureusandBacillussubtilis.The antibacterial activities toStaphylococcusaureuswas found to be disappeared in the MCL-T in which tryptophan residues,-S-S-, -SH and tyrosine residueswere chemically modified.The chemicalmodification of-S-S-in the MCL-T led to less effects on the antibacterial activities againstBacillussubtilis,but the chemicalmodification of its-SH,tryptophan residues and tyrosine residues resulted in losing antibacterial activities againstBacillussubtilis.The findings indicate that the patterns of the MCL-T amino acid residues is involved in the antibacterial activities.
2012, Vol. 27 
