Yacoub Haitham A, El-Hamidy Salem M, Mahmoud Maged M, Baeshen Mohamed Nabih, Almehdar Hussein A, Uversky Vladimir N, Redwan Elrashdy M, Al-Maghrabi Omar A, Elazzazy Ahmed M
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.
Biochem Cell Biol. 2016 Apr;94(2):176-87. doi: 10.1139/bcb-2015-0121. Epub 2015 Dec 16.
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.
在本研究中，我们鉴定了沙特阿拉伯鸡体内β-防御素-9的表达模式，评估了合成鸡β-防御素-9（sAvBD-9）对病原菌和真菌的抗菌活性，并研究了sAvBD-9对细菌细胞的作用方式。沙特鸡的AvBD-9基因编码一个由67个氨基酸组成的多肽，该多肽与鸭、鹌鹑和鹅体内的多肽高度相似（分别为97%、86%和87%），与哺乳动物防御素的序列相似性较低。AvBD-9在沙特鸡的各种器官和组织中表达，可抑制革兰氏阴性菌和革兰氏阳性菌的生长，还对单细胞和多细胞真菌（黄曲霉、黑曲霉和白色念珠菌）具有活性。sAvBD-9完全抑制了革兰氏阳性菌和革兰氏阴性菌菌株以及白色念珠菌的生长。sAvBD-9的溶血作用有限。透射电镜的形态学分析显示，sAvBD-9可诱导金黄色葡萄球菌和宋内志贺氏菌细胞缩短和肿胀，在其包膜上形成孔洞和深坑，并导致其细胞质内容物释放。我们的数据揭示了sAvBD-9在制药行业的潜在应用。
