Structure and membrane interactions of chionodracine, a piscidin-like antimicrobial peptide from the icefish Chionodraco hamatus.
Chionodracine (Cnd) is a 22-residue peptide of the piscidin family expressed in the gills of the Chionodraco hamatus as protection from bacterial infections. Here, we report the effects of synthetic Cnd on both Psychrobacter sp. TAD1 and Escherichia coli bacteria, as well as membrane models. We found that Cnd perforates the inner and outer membranes of Psychrobacter sp. TAD1, making discrete pores that cause the cellular content to leak out. Membrane disruption studies using intrinsic and extrinsic fluorescence spectroscopy revealed that Cnd behaves similarly to other piscidins, with comparable membrane partition coefficients. Membrane accessibility assays and structural studies using NMR in detergent micelles show that Cnd adopts a canonical topology of antimicrobial helical peptides, with the hydrophobic face toward the lipid environment and the hydrophilic face toward the bulk solvent. The analysis of Cnd free energy of binding to vesicles with different lipid contents indicates a preference for charged phospholipids and a more marked binding to native E. coli extracts. Taken with previous studies on piscidin-like peptides, we conclude that Cnd first adsorbs to the membrane, and then forms pores together with membrane fragmentation. Since Cnd has only marginal hemolytic activity, it constitutes a good template for developing new antimicrobial agents.
Department for Innovation in Biological, Agro-food, and Forest Systems, University of Tuscia, Viterbo 01100, Italy.
Cristina
C
Olivieri
Department for Innovation in Biological, Agro-food, and Forest Systems, University of Tuscia, Viterbo 01100, Italy.
Francesco
F
Buonocore
Department for Innovation in Biological, Agro-food, and Forest Systems, University of Tuscia, Viterbo 01100, Italy.
Simona
S
Picchietti
Section of Electron Microscopy, Great Equipment Center, University of Tuscia, Viterbo 01100, Italy.
Anna Rita
AR
Taddei
Department for Innovation in Biological, Agro-food, and Forest Systems, University of Tuscia, Viterbo 01100, Italy.
Chiara
C
Bernini
Department for Innovation in Biological, Agro-food, and Forest Systems, University of Tuscia, Viterbo 01100, Italy.
Giuseppe
G
Scapigliati
Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis 55455, USA; Department of Chemistry, University of Minnesota, Minneapolis 55455, USA.
Alysha A
AA
Dicke
Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis 55455, USA; Department of Chemistry, University of Minnesota, Minneapolis 55455, USA.
Vitaly V
VV
Vostrikov
Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis 55455, USA; Department of Chemistry, University of Minnesota, Minneapolis 55455, USA. Electronic address: vegli001@umn.edu.
Gianluigi
G
Veglia
Department for Innovation in Biological, Agro-food, and Forest Systems, University of Tuscia, Viterbo 01100, Italy. Electronic address: porcelli@unitus.it.
Fernando
F
Porcelli
D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry* / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry* / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects* / Q000648:ultrastructure; D002463:Cell Membrane Permeability / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D005452:Fluoresceins / Q000378:metabolism; D005453:Fluorescence; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010473:Perciformes / Q000378:metabolism*; D010713:Phosphatidylcholines / Q000737:chemistry; D010715:Phosphatidylglycerols / Q000737:chemistry; D011193:Potassium Iodide / Q000737:chemistry; D044096:Psychrobacter / Q000187:drug effects; D013696:Temperature
D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D005452:Fluoresceins; D008823:Micelles; D010713:Phosphatidylcholines; D010715:Phosphatidylglycerols; C000600684:chionodracine, Chionodraco hamatus; D011193:Potassium Iodide; C060037:1-palmitoyl-2-oleoylglycero-3-phosphoglycerol; C028694:1-palmitoyl-2-oleoylphosphatidylcholine; C007740:fluorexon
Antimicrobial peptides; Fluorescence; Membrane permeabilization; NMR; Piscidins; Structure