title: Caenopore-5: the three-dimensional structure of an antimicrobial protein from Caenorhabditis elegans.
abstract: The caenopore-5 protein encoded by the spp-5 gene is one of the 33 caenopores identified in Caenorhabditis elegans and is a pore-forming peptide which plays an important role in the elimination of Escherichia coli ingested by the worm. Thus, caenopore-5 appears to contribute to the nutrition of the worm while simultaneously protecting the organism against pathogens. Here, three-dimensional heteronuclear NMR spectroscopy was used to solve the solution structure of caenopore-5. The NMR data revealed that two conformers of caenopore-5 exist in solution which differ by the isomerization of the peptide bond of Pro-81. The overall structure of the two caenopore-5 conformers consists of five amphiphatic helices connected by three disulfide bonds. The five helices are arranged in a folded leaf which is the characteristic signature of the SAPLIP family. The structure presented here is the first of an effector protein of the defensive system elucidated for the well-known model organism C. elegans.
authors.affiliation: Institute of Biochemistry, Christian-Albrechts-University Kiel, Olshausenstr. 40, 24098 Kiel, Germany.
authors.forename: Justyna
authors.initials: J
authors.lastname: Mysliwy
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Dingley
authors.forename: Mareike
authors.initials: M
authors.lastname: Stanisak
authors.forename: Sascha
authors.initials: S
authors.lastname: Jung
authors.forename: Inken
authors.initials: I
authors.lastname: Lorenzen
authors.forename: Thomas
authors.initials: T
authors.lastname: Roeder
authors.forename: Matthias
authors.initials: M
authors.lastname: Leippe
authors.forename: Joachim
authors.initials: J
authors.lastname: Grötzinger
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000737:chemistry* / Q000276:immunology; D029742:Caenorhabditis elegans Proteins / Q000737:chemistry* / Q000276:immunology; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000737:chemistry; D020836:Protein Structure, Quaternary; D020539:Sequence Analysis, Protein
chemical_list: D029742:Caenorhabditis elegans Proteins; D020033:Protein Isoforms