Isolation And Characterization Of Acipenser Schrenki Brandt Skin Mucus And Its Lectins

Sturgeons is the only large-scale cartilage scleroderma fish existing in class Teleosta,with a long age of sexual maturity.Because of its unique economic value and biological characteristics it has attracted much attention.Skin mucus of fish is of great significance to its immune defense,osmotic pressure maintenance and metabolism.This study conducted proteomic analysis of the skin mucus of Acipenser schrenki Brandt in order to explore the molecular diversity and functional mechanism of it.Fish lectin mainly exists in the serum,muscle,blood cells and fertilized eggs of fish.At present,there is no report on lectin from mucus of Acipenser schrenki Brandt.In this study,Acipenser schrenki Brandt lectin(ASL)was extracted and its hemagglutinating activity,sugar specificity,antibacterial activity and its effect on cells were researched,aiming to investigate the biological activity of the novel lectin and provide basic material for the evolution of new lectins.The main results are as follows:1.The proteins from the mucus of Acipenser schrenki Brandt were identified by proteomics technology.There were 3283 kinds of proteins.Through quantitative analysis,3003 kinds of proteins were obtained.These proteins are mainly about structure,immune,catalytic,apoptosis and antibacterial activity.The molecular weight of these proteins is mainly between 10-60 k Da,accounting for more than 50% of total protein.Mucin is mainly distributed in the nucleus and cytoplasm,accounting for 41% and 30.2%,and a small part is distributed outside the cell,accounting for 8.1%.It has binding and catalytic activity,signal and immunity.Among them,proteins with antioxidant,antibacterial and anticancer activity interact.2.Acipenser schrenki Brandt lectin(ASL)with hemagglutinating activity was isolated by normal saline extraction,80% saturated ammonium sulfate precipitation and Cellulose DE-52,and the hemagglutinating activity was inhibited by four sugars and glycoproteins.The ASL treated with mercaptoethanol or untreated showed a protein band on SDS-PAGE with a molecular weight of 13 k Da.The amino acid composition analysis of ASL showed that it contained a variety of amino acids,among which threonine was the highest,accounting for7.72%.It was followed by glutamate or glutamine,accounting for 7.62% and aspartic acid or asparagine is accounted for 5.23%.3.Acipenser schrenki Brandt lectin(ASL)showed inhibitory activity on Staphylococcus aureus,which inhibited hexose monophosphate pathway(HMP)in its glucose oxidation metabolic pathway.Acipenser schrenki Brandt lectin(ASL)has the potential to promote the proliferation of Saccharomyces cerevisiae,which can diminish the content of residual sugar and the p H of fermentation liquor.