title: Biocidal activity of chicken defensin-9 against microbial pathogens.
abstract: In this study we identified the expression patterns of β-defensin-9 in chickens from Saudi Arabia, evaluated the antimicrobial activities of synthetic chicken β-defensin-9 (sAvBD-9) against pathogenic bacteria and fungi, and investigated the mode of action of sAvBD-9 on bacterial cells. The AvBD-9 gene of Saudi chickens encodes a polypeptide of 67 amino acids, which is highly similar to the polypeptide in duck, quail, and goose (97%, 86%, and 87%, respectively) and shares a low sequence similarity with the mammalian defensins. AvBD-9 is expressed in various organs and tissues of Saudi chickens and inhibits the growth of both Gram-negative and Gram-positive bacteria, as well as showing activity against unicellular and multicellular fungi (Aspergillus flavus, A. niger, and Candida albicans). sAvBD-9 completely inhibited the growth of both Gram-positive and Gram-negative bacterial strains as well as Candida albicans. The haemolytic effects of sAvBD-9 were limited. Morphological analysis by TEM revealed that sAvBD-9 induces shortening and swelling of Staphylococcus aureus and Shigella sonni cells, opens holes and deep craters in their envelopes, and leads to the release of their cytoplasmic content. Our data shed light on the potential applications of sAvBD-9 in the pharmaceutical industry.
authors.affiliation: a Biological Sciences Department, Faculty of Science, University of Jeddah, Jeddah, Saudi Arabia.|b Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.|c National Research Centre, Dokki, Gizza, P.O. Box 12622, Egypt.
authors.forename: Haitham A
authors.initials: HA
authors.lastname: Yacoub
authors.affiliation: b Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Salem M
authors.initials: SM
authors.lastname: El-Hamidy
authors.affiliation: d King Fahd Medical Research Center, King Abdulaziz University, P.O. Box 80216, Jeddah 21589, Saudi Arabia.|i Department of Molecular Genetics and Enzymology, Devision of Human Genetocs and Genome Research, National Research Centre, Dokki, Gizza, P.O. Box 12622, Egypt.
authors.forename: Maged M
authors.initials: MM
authors.lastname: Mahmoud
authors.affiliation: a Biological Sciences Department, Faculty of Science, University of Jeddah, Jeddah, Saudi Arabia.|b Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Mohamed Nabih
authors.initials: MN
authors.lastname: Baeshen
authors.affiliation: b Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Hussein A
authors.initials: HA
authors.lastname: Almehdar
authors.affiliation: b Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.|e Institute for Biological Instrumentation, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia.|g Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA.
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Uversky
authors.affiliation: b Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.|f Therapeutic and Protective Proteins Laboratory, Protein Research Department, Genetic Engineering and Biotechnology Research Institute, City for Scientific Research and Technology Applications, New Borg EL-Arab 21934, Alexandria, Egypt.
authors.forename: Elrashdy M
authors.initials: EM
authors.lastname: Redwan
authors.affiliation: a Biological Sciences Department, Faculty of Science, University of Jeddah, Jeddah, Saudi Arabia.
authors.forename: Omar A
authors.initials: OA
authors.lastname: Al-Maghrabi
authors.affiliation: a Biological Sciences Department, Faculty of Science, University of Jeddah, Jeddah, Saudi Arabia.|h Department of Chemistry of Natural and Microbial Products, Division of Pharmaceutical and Drug Industries, National Research Centre, Dokki, Gizza, P.O. Box 12622, Egypt.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Elazzazy
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D000935:Antifungal Agents / Q000737:chemistry / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*; D002645:Chickens; D005658:Fungi / Q000187:drug effects*; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000254:growth & development; D006094:Gram-Positive Bacteria / Q000187:drug effects* / Q000254:growth & development; D008826:Microbial Sensitivity Tests; D016415:Sequence Alignment; D023083:beta-Defensins / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D023181:Antimicrobial Cationic Peptides; D023083:beta-Defensins
keywords: antibacterial peptide; antifungal peptide; defensin; défensine; défensine synthétique; peptide antibactérien; peptide antifongique; synthetic defensin