Design, characterization and expression of a novel hybrid peptides melittin (1-13)-LL37 (17-30)

Mol Biol Rep. 2014 Jul;41(7):4163-9. doi: 10.1007/s11033-013-2900-0. Epub 2014 May 29.

Abstract

Hybridizing of different antimicrobial peptides (AMPs) has been a common practice for obtaining novel hybrid AMPs with elevated antibacterial activity but minimized cytotoxicity. The hybrid peptides melittin (1-13)-LL37 (17-30) (M-L) combining the hydrophobic N-terminal fragment of melittin (M) with the core antibacterial fragment of LL37 (L), was designed for the first time to explore its antibacterial activity and hemolytic activity against bacteria and sheep erythrocyte respectively. Results showed that M-L had an even more potent antibacterial activity against all indicator strains (especially gram-positive bacteria) than M and L, whereas didn't exhibit hemolytic activity to sheep erythrocytes, implying M-L can be served as a potential therapeutic drug to substitute traditional antibiotics. However the high expense of biosynthesis limited its further research, therefore fusion expression of M-L was carried out in Escherichia coli (E. coli) for overproducing the hybrid peptide so as to solve the problem. The DNA sequence encoding M-L with preferred codons was cloned into the pET-SUMO vector for protein expression in E. coli BL21 (DE3). After IPTG induction, approximately 165 mg soluble fusion protein SUMO-M-L was recovered per liter supernatant of the fermentation ultrasonic lysate using Ni-NTA Sepharose column (92 % purity). And 23 mg recombinant M-L was obtained per liter culture after cleavage of SUMO protease and purification of Ni-NTA Sepharose column. In sum, this research not only supplied an effective approach for overproducing hybrid peptide M-L, but paved the way for its further exploration on pharmaceutical potential and medical importance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Anti-Bacterial Agents / biosynthesis*
  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology
  • Antimicrobial Cationic Peptides
  • Bees
  • Cathelicidins / chemistry*
  • Cathelicidins / genetics
  • Cathelicidins / pharmacology
  • Cells, Cultured
  • Drug Design
  • Erythrocytes / cytology
  • Erythrocytes / drug effects
  • Escherichia coli / drug effects
  • Escherichia coli / genetics
  • Escherichia coli / growth & development
  • Gene Expression
  • Hemolysis / drug effects
  • Humans
  • Listeria monocytogenes / drug effects
  • Listeria monocytogenes / growth & development
  • Melitten / chemistry*
  • Melitten / genetics
  • Melitten / pharmacology
  • Micrococcus luteus / drug effects
  • Micrococcus luteus / growth & development
  • Molecular Sequence Data
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / pharmacology
  • Sheep
  • Staphylococcus aureus / drug effects
  • Staphylococcus aureus / growth & development

Substances

  • Anti-Bacterial Agents
  • Antimicrobial Cationic Peptides
  • Cathelicidins
  • Recombinant Fusion Proteins
  • Melitten