Design of novel analogues with potent antibiotic activity based on the antimicrobial peptide, HP(2-9)-ME(1-12).
To develop novel antibiotic peptides useful as therapeutic drugs, a number of analogues were designed to increase the hydrophobic helix region either by Trp-substitution or net positive charge increase by Lys-substitution, from HP(2-9)-ME(1-12). The antibiotic activities of these peptides were evaluated using bacterial (Salmonella tryphimurium, Proteus vulgaris, Bacillus subtilis and Staphylococcus aureus), fungi (Saccharomyces cerevisiae, Trichosporon beigelii and Candida albicans), tumor and human erythrocyte cells. The substitution of Lys for Thr at position 18 and 19 of HP(2-9)-ME(1-12) (HM5) increased activity against Proteus vulgaris and fungal strains without hemolysis. In contrast, substitution of Trp for Lys and Thr at positions 2, 15 and 19 of HP(2-9)-ME(1-12), respectively (HM3 and HM4), decreased activity but increased hemolysis against human erythrocytes. This suggests that an increase in positive charge increases antimicrobial activity whereas an increase in hydrophobicity by introducing Trp residues at C-terminus of HP(2-9)-ME(1-12) causes a hemolytic effect. Circular dichroism spectra suggested that the alpha-helical structure of these peptides plays an important role in their antibiotic effect but that the alpha-helical property is not connected with the enhanced antibiotic activity.
Park
Yoonkyung
Y
Research Center for Proteineous Materials, School of Medicine, Chosun University, 375 Seosuk-Dong, Dong-Ku, Kwangju 501-759, Korea.
Kim
Hee Nam
HN
Park
Soon Nang
SN
Jang
Seung-Hwan
SH
Choi
Cheol-Hee
CH
Lim
Hak-Tae
HT
Hahm
Kyung-Soo
KS
D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry*; D001426:Bacterial Proteins / Q000138:chemical synthesis / Q000737:chemistry*; D015195:Drug Design; D016480:Helicobacter pylori / Q000737:chemistry; D008555:Melitten / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D010455:Peptides; D017433:Protein Structure, Secondary; D012269:Ribosomal Proteins / Q000138:chemical synthesis / Q000737:chemistry*; D013329:Structure-Activity Relationship
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D010455:Peptides; D012269:Ribosomal Proteins; C028546:ribosomal protein L1; D008555:Melitten