title: Solution and solid-state NMR structural studies of antimicrobial peptides LPcin-I and LPcin-II.
abstract: Lactophoricin (LPcin-I) is an antimicrobial, amphiphatic, cationic peptide with 23-amino acid residues isolated from bovine milk. Its analogous peptide, LPcin-II, lacks six N-terminal amino acids compared to LPcin-I. Interestingly, LPcin-II does not display any antimicrobial activity, whereas LPcin-I inhibits the growth of both Gram-negative and Gram-positive bacteria without exhibiting any hemolytic activity. Uniformly (15)N-labeled LPcin peptides were prepared by the recombinant expression of fusion proteins in Escherichia coli, and their properties were characterized by electrospray ionization mass spectrometry, circular dichroism spectroscopy, and antimicrobial activity tests. To understand the structure-activity relationship of these two peptides, they were studied in model membrane environments by a combination of solution and solid-state NMR spectroscopy. We determined the tertiary structure of LPcin-I and LPcin-II in the presence of dodecylphosphorylcholine micelles by solution NMR spectroscopy. Magnetically aligned unflipped bicelle samples were used to investigate the structure and topology of LPcin-I and LPcin-II by solid-state NMR spectroscopy.
authors: Department of Chemistry and Protein Research Center for Bio-Industry, Hankuk University of Foreign Studies, Yong-In, Korea.
authors: Tae-Joon
authors: TJ
authors: Park
authors: Ji-Sun
authors: JS
authors: Kim
authors: Hee-Chul
authors: HC
authors: Ahn
authors: Yongae
authors: Y
authors: Kim
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D002417:Cattle; D002942:Circular Dichroism; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D017433:Protein Structure, Secondary; D012996:Solutions; D021241:Spectrometry, Mass, Electrospray Ionization; D013329:Structure-Activity Relationship
chemical_list: D023181:Antimicrobial Cationic Peptides; D012996:Solutions