title: Two novel duck antibacterial peptides, avian beta-defensins 9 and 10, with antimicrobial activity.
abstract: Two novel avian beta-defensins (AvBDs) isolated from duck liver were characterized and their homologies with other AvBDs were analyzed. They were shown to be duck AvBD9 and AvBD10. The mRNA expression of the two genes was analyzed in 17 different tissues from 1-28-dayold ducks. AvBD9 was differentially expressed in the tissues, with especially high levels of expression in liver, kidney, crop, and trachea, whereas AvBD10 was only expressed in the liver and kidney of ducks at all the ages investigated. We produced and purified GST-tagged recombinant AvBD9 and AvBD10 by expressing the two genes in Escherichia coli. Both recombinant proteins exhibited antimicrobial activity against several bacterial strains. The results revealed that both recombinant proteins retained their antimicrobial activities against Staphylococcus aureus under a range of different temperatures (-70 degrees C -100 degrees C) and pH values (pH 3-12).
authors.affiliation: Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China.
authors.forename: Deying
authors.initials: D
authors.lastname: Ma
authors.forename: Wenyan
authors.initials: W
authors.lastname: Liao
authors.forename: Ruiqin
authors.initials: R
authors.lastname: Wang
authors.forename: Zongxi
authors.initials: Z
authors.lastname: Han
authors.forename: Shengwang
authors.initials: S
authors.lastname: Liu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000008:administration & dosage* / Q000302:isolation & purification; D003001:Cloning, Molecular; D003426:Crop, Avian / Q000378:metabolism; D004372:Ducks; D004926:Escherichia coli / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics; D017385:Sequence Homology; D013211:Staphylococcus aureus / Q000187:drug effects; D014132:Trachea / Q000378:metabolism; D023083:beta-Defensins / Q000008:administration & dosage* / Q000302:isolation & purification / Q000502:physiology*
chemical_list: D000890:Anti-Infective Agents; D011993:Recombinant Fusion Proteins; D023083:beta-Defensins