The Research Of The Antimicrobial Peptides Crustin From Portunus Trituberculatus

In preliminary studies We cloned a type I Crustin gene from Portunus trituberculatusblood cells. We also constructed the eukaryotic expression vector pVT102U/α-rCrustinI.We get the engineering yeast which Used to express the gene of the recombinantantibacterial peptide rCrustinI.In this study, We cultured yeast engineered bacteria in a suitable medium and cultureconditions, the expression of antibacterial peptide genes and antimicrobial peptide wassecreted of the yeast.Content of antimicrobial peptides in the fermentation broth is1.087mg/L. We purified fermentation broth use of Centrifugal, ammonium sulfate precipitation,Ion exchange chromatography, Freeze-dried, Water-soluble, HPLC, freeze-.We use thesemethods to get the pure product of the recombinant antimicrobial peptidesrCrustinI.Wefound that recombinant antimicrobial peptides rCrustinI is different from the others Crustinantimicrobial peptides We found that recombinant antimicrobial peptides rcrustinI not onlyhave antibacterial activityagainst on Gram-positive bacteria, but also have antibacterialactivityagainst on Gram-negative bacteria.By amplification of the genomic DNA of the Portunus trituberculatus,We analyzedthe genomic DNA sequence of the Portunus trituberculatus.We speculate that the CrustinIand CrustinIII are two alternative splicing.We studied Expression of hthe two alternative splicing CrustinI and CrustinIII whitchin Various tissues of the liver, spleen, gills, eyes by semi-quantitative RT-PCR. The studyfound that The difference of the expression of CrustinI and CrustinIII in various tissues,before and after induction.