title: Recombinant expression, synthesis, purification, and solution structure of arenicin.
abstract: Arenicins are 21-residue cationic antimicrobial peptides, isolated from marine polychaeta Arenicola marina. In order to determine a high-resolution three-dimensional structure of arenicin-2, the recombinant peptide was overexpressed as a fused form in Escherichia coli. Both arenicin isoforms were synthesized using the Fmoc-based solid-phase strategy. Recombinant and synthetic arenicins were purified, and their antimicrobial and spectroscopic properties were analyzed. NMR investigation shows that in water solution arenicin-2 displays a prolonged beta-hairpin, formed by two antiparallel beta-strands and stabilized by one disulfide and nine hydrogen bonds. A significant right-handed twist in the beta-sheet is deprived the peptide surface of amphipathicity. CD spectroscopic analysis indicates that arenicin-2 binds to the SDS and DPC micelles, and conformation of the peptide is significantly changed upon binding. Arenicin strongly binds to anionic lipid (POPE/POPG) vesicles in contrast with zwitterionic (POPC) ones. These results suggest that arenicins are membrane active peptides and point to possible mechanism of their selectivity toward bacterial cells.
authors.affiliation: Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Str., 16/10, 117997 Moscow, Russia. ovch@ibch.ru
authors.forename: Tatiana V
authors.initials: TV
authors.lastname: Ovchinnikova
authors.forename: Zakhar O
authors.initials: ZO
authors.lastname: Shenkarev
authors.forename: Kirill D
authors.initials: KD
authors.lastname: Nadezhdin
authors.forename: Sergey V
authors.initials: SV
authors.lastname: Balandin
authors.forename: Maxim N
authors.initials: MN
authors.lastname: Zhmak
authors.forename: Irina A
authors.initials: IA
authors.lastname: Kudelina
authors.forename: Ekaterina I
authors.initials: EI
authors.lastname: Finkina
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Kokryakov
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Arseniev
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003198:Computer Simulation; D008956:Models, Chemical; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D011077:Polychaeta / Q000378:metabolism*; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000648:ultrastructure
chemical_list: D010455:Peptides; D011994:Recombinant Proteins