The Design And Synthesis Of Antimicrobial Peptide KL-18 And Study On Its In Vitro Actions In Antibiosis And Anti-tumor

Objectives: To obtain a novel antimicrobial peptide(AMP), we took the recently discoveried antimicrobial peptide LL-37 as a skeleton. According to the relationships between the structure and the function of the antimicrobial peptide, we selected the essential sequence which displayed antibacterial function, analyzed the sequence and replaced some amino acids with other ones. Then observed its antibacterial abilities and its influences to tumour cells to evaluate its value in application. Methods:(1) We obtained the amino acid sequence of LL-37 from PubMed. Then we analyzed its structure by some softwares which were used to analyze protein structures, and discovered its essential a -helix sequence. After analyzing its characters of hydrophobicity and helix, we replaced some amino acids with other ones. The novel designed antibacterial peptide was artificially synthesized in a company.(2) We Selected Escherichia coli JM109 , Staphylococcus aureus(clinical) , Staphylococcus albus(clinical) , Enterococcus faecalis ATCC 29212 and Fluoroquinolones resistant Enterococcus faecalis(FREF) in antibacterial experiment. We applied the method of microdilution to test the MIC of the new AMP and Penicillin or Ampicillin to the five bacteria strains.(3)Co-incubated the new peptide and the HepaG2 cells as well as the THP-1 cells in 96-well microtest tissue culture plate, in order to test the...