Function And Related Studies Of A Novel Gene Encoding Antimicrobial Peptide

A novel gene encoding human glycine-rich protein (hGlyrichin) was amplified from human fetal liver cDNA library, which was highly homologue to our first cloned mouse gene mL52(GenBank number: AY028425). Based on the bioinformatics analysis and primary experimental results of hGlyrichin with antibacterial activity, a series of peptides were synthesized according to the bioinformatic analysis in order to find its functional domain. The results have shown that a peptide (pCM-19) within the 42^nd and 60^th amino acids of hGlyrichin has the antibacterial activity. Thereafter, the spectrum of antibacterial activity, the antibacterial mechanisms and hemolytic effects of pCM-19 were further investigated. The results have demonstrated that pCM-19 has the antibacterial activity against not only the bacteria laborotary using but also those bacteria with pathogenesis potential, including yersinia pestis, Salmonella typhimurium, Staphylococcus aureus, Meningococcus and Pseudomonas aeruginosa, More interesting, pCM-19 could kill both the bacteria with transferred ampicillin-resistant gene and genetically mutant bacterial strains with ampicillin-resistant capacity. These results have demonstrated that pCM-19 has broad spectrum of antibacterial effects, implying that pCM-19 has splendid future for its application. The dose-effects of pCM-19 against bacteria were consistent with that reported by Sunkyu Kim, in which a antimicrobial peptide, gaegurin 6 was studied, suggesting that the antibacterial activity could be found only when the concentration of pCM-19 reached to a threshold dosage. The stability of pCM-19 was also tested through heating in different times, prolonged storage time up to 80 days at 4 degrees centigrade in liquid state and treatment with trypsin, resulting in relative stable state concerning the activity against bacteria. In order to study the antibacterial machenisms of pCM-19, FACS analysis and...