Li Jiale, Islam Samiul, Guo Pengfei, Hu Xiaoqing, Dong Wubei
Department of Plant Pathology, College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province, Huazhong Agricultural University, Wuhan 430070, China.
Int J Mol Sci. 2020 Nov 18;21(22):8722. doi: 10.3390/ijms21228722.
Antimicrobial genes are distributed in all forms of life and provide a primary defensive shield due to their unique broad-spectrum resistance activities. To better isolate these genes, we used the expression system as the host cells to build Griff cDNA libraries and screen potential candidate genes from the library at higher flux using built-in indicator bacteria. We observed that the antimicrobial peptides OrR214 and OrR935 have strong antimicrobial activity against a variety of Gram-positive and Gram-negative bacteria, as well as several fungal pathogens. Owing to their high thermal and enzymatic stabilities, these two peptides can also be used as field biocontrol agents. Furthermore, we also found that the peptide OrR214 (MIC 7.7-10.7 μM) can strongly inhibit bacterial growth compared to polymyxin B (MIC 5-25 μM) and OrR935 (MIC 33-44 μM). The cell flow analysis, reactive oxygen burst, and electron microscopy (scanning and transmission electron microscopy) observations showed that the cell membranes were targeted by peptides OrR214 and OrR935, which revealed the mode of action of bacteriostasis. Moreover, the hemolytic activity, toxicity, and salt sensitivity experiments demonstrated that these two peptides might have the potential to be used for clinical applications. Overall, OrR214 and OrR935 antimicrobial peptides have a high-throughput bacteriostatic activity that acts as a new form of antimicrobial agent and can be used as a raw material in the field of drug development.
抗菌基因分布于所有生命形式中，因其独特的广谱抗性活性而提供了一道主要的防御屏障。为了更好地分离这些基因，我们使用表达系统作为宿主细胞构建格里菲思cDNA文库，并利用内置指示菌以更高通量从文库中筛选潜在的候选基因。我们观察到抗菌肽OrR214和OrR935对多种革兰氏阳性和革兰氏阴性细菌以及几种真菌病原体具有很强的抗菌活性。由于它们具有高热稳定性和酶稳定性，这两种肽还可作为田间生物防治剂。此外，我们还发现与多粘菌素B（MIC 5 - 25 μM）和OrR935（MIC 33 - 44 μM）相比，肽OrR214（MIC 7.7 - 10.7 μM）能强烈抑制细菌生长。细胞流式分析、活性氧爆发以及电子显微镜（扫描和透射电子显微镜）观察表明，肽OrR214和OrR935靶向细胞膜，这揭示了其抑菌作用方式。此外，溶血活性、毒性和盐敏感性实验表明这两种肽可能具有临床应用潜力。总体而言，OrR214和OrR935抗菌肽具有高通量抑菌活性，作为一种新型抗菌剂，可作为药物开发领域的原料。
