title: Two antimicrobial and nematicidal peptides derived from sequences encoded Picea sitchensis.
abstract: Two antimicrobial peptides (piceain 1 and 2) derived from sequences encoded Picea sitchensis are identified. Their amino acid sequences are KSLRPRCWIKIKFRCKSLKF and RPRCWIKIKFRCKSLKF, respectively. One intra-molecular disulfide bridge is formed by these two half-cysteines in both piceain 1 and 2. Antimicrobial activities of synthesized piceains against several kinds of microorganisms were tested. They showed antimicrobial activities against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and fungus Candida albicans but little antimicrobial activity against Bacillus subtilis. The results of nematicidal test showed they exerted strong nematicidal activities against Caenorhabditis elegans, following exposure for 5 h at concentrations as low as 10 µg/ml. They had weak hemolytic abilities against human and rabbit red cells. At the concentration of 250 µg/ml, they induced red cell hemolysis of less than 5%. Circular dichroism spectra of the two antimicrobial peptides were investigated in several solutions. Their main secondary structure components are β-sheet and random. The current work provides a novel family of antimicrobial and nematicidal peptides with unique disulfided loop containing nine amino acid residues.
authors.affiliation: Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Life Sciences College of Nanjing Agricultural University, Jiangsu, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Liu
authors.forename: Lixian
authors.initials: L
authors.lastname: Mu
authors.forename: Huan
authors.initials: H
authors.lastname: Liu
authors.forename: Lin
authors.initials: L
authors.lastname: Wei
authors.forename: Tianhua
authors.initials: T
authors.lastname: Yan
authors.forename: Ming
authors.initials: M
authors.lastname: Chen
authors.forename: Keyun
authors.initials: K
authors.lastname: Zhang
authors.forename: Jianxu
authors.initials: J
authors.lastname: Li
authors.forename: Dewen
authors.initials: D
authors.lastname: You
authors.forename: Ren
authors.initials: R
authors.lastname: Lai
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry* / Q000494:pharmacology; D000969:Antinematodal Agents / Q000737:chemistry* / Q000494:pharmacology; D004912:Erythrocytes / Q000187:drug effects; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry* / Q000235:genetics / Q000494:pharmacology; D028222:Picea / Q000737:chemistry* / Q000235:genetics; D017433:Protein Structure, Secondary; D011817:Rabbits
chemical_list: D000890:Anti-Infective Agents; D000969:Antinematodal Agents; D010455:Peptides