College of Food Science and Engineering, Gansu Agricultural University, No. 1 Yingmen Village, Anning District, Lanzhou, 730070, Gansu, China.
World J Microbiol Biotechnol. 2018 Jan 4;34(2):21. doi: 10.1007/s11274-017-2392-5.
Public concern for food safety and environmental issues and the increase in fungicide-resistant pathogen have enhanced the interest in developing alternative methods to fungicides to control postharvest fruit decay. In this study, a bacterial strain isolated from stale potato vermicelli was identified as Bacillus pumilus HN-10 based on morphological characteristics and 16S rRNA gene sequence analysis. Furthermore, two novel cationic antifungal peptides named P-1 and P-2 were purified from B. pumilus HN-10 using macroporous adsorbent resin AB-8, Sephadex G-100 chromatography, and reversed-phase high-performance liquid chromatography. The primary structure of P-1 and P-2, which were proved to be novel antifungal peptides by BLAST search in NCBI database, was PLSSPATLNSR and GGSGGGSSGGSIGGR with a molecular weight of 1142.28 and 1149.14 Da, respectively, as indicated by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Both P-1 and P-2 exhibited strong antifungal activity against Trichothecium roseum with minimum inhibitory concentrations starting from 1 μg/mL. The two novel antifungal peptides were stable below 80 °C for 2 h, but lost their activity in 15 min at 121 °C. In addition, they were resistant to the proteolytic action of pepsin, trypsin, and papain, and stable within a wide range of pH (2.0-12.0). These results showed that P-1 and P-2 are novel cationic antifungal peptides with specific activity against T. roseum.
公众对食品安全和环境问题的关注以及抗真菌剂的病原体增加，促使人们对开发替代杀菌剂的方法产生了浓厚的兴趣，以控制采后水果腐烂。在本研究中，根据形态特征和 16S rRNA 基因序列分析，从 stale potato vermicelli 中分离到的一株细菌菌株被鉴定为 Bacillus pumilus HN-10。此外，使用大孔吸附树脂 AB-8、Sephadex G-100 色谱和反相高效液相色谱从 Bacillus pumilus HN-10 中纯化了两种新型阳离子抗真菌肽，命名为 P-1 和 P-2。通过在 NCBI 数据库中进行 BLAST 搜索，证明 P-1 和 P-2 是新型抗真菌肽，其一级结构分别为 PLSSPATLNSR 和 GGSGGGSSGGSIGGR，分子量分别为 1142.28 和 1149.14 Da，基质辅助激光解吸/电离飞行时间质谱仪（matrix-assisted laser desorption/ionization time-of-flight mass spectrometry）。P-1 和 P-2 对粉红单端孢霉（Trichothecium roseum）均表现出较强的抗真菌活性，最小抑菌浓度（MIC）均从 1μg/mL 开始。两种新型抗真菌肽在 80°C 以下稳定 2 小时，但在 121°C 下 15 分钟内失去活性。此外，它们能抵抗胃蛋白酶、胰蛋白酶和木瓜蛋白酶的蛋白水解作用，在 pH 值（2.0-12.0）范围内稳定。这些结果表明，P-1 和 P-2 是针对粉红单端孢霉的新型阳离子抗真菌肽，具有特定的活性。
