Key Lab of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Lab of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China.
State Key Laboratory of Food Nutrition and Safety, Tianjin 300457, China.
Molecules. 2018 Sep 3;23(9):2246. doi: 10.3390/molecules23092246.
HZ1 was identified from Chinese traditional fermented milk, and angiotensin converting enzyme inhibitory peptide was separated from its culture in our previous work. Here, LGH2 was a novel AMP, identified from the genome of HZ1. Altogether, roughly 52.76% of LGH2 was α -helical, with the remainder in β -strand and random coil in 50% TFE solution tested by CD. The peptide was also an amphipathic and cationic molecule, which was composed of 20 amino acid residues. The similarity of the amino acid sequence between LGH2 and Temporin-RN3 was highest. Then, the peptide successfully expressed in Rossetta (DE3) pLysS using the SUMO fusion expression system and purified by chromatography technologies. The molecular weight of the peptide was 2448 Da determined by MALDI-TOF MS. Antimicrobial tests showed that the peptide has strong activities against G+ bacteria, special for (MIC = 4 μM). The toxicity assay showed that the peptide exhibits a low hemolytic activity against sheep red blood cells. The antimicrobial mechanisms of LGH2 against pathogens were further investigated by dye leakage, CLSM, SEM, and FCM assays. We found that LGH2 can bind to the cell membrane, and destroy its integrity. These significant results indicate that LGH2 has great potential to treat the infections caused by pathogenic bacteria such as , and it provides a new template to improve antimicrobial peptides targeting antibiotic-resistant pathogenic bacteria.
HZ1 是从中国传统发酵乳中分离得到的，我们之前的工作中从其培养物中分离出了血管紧张素转换酶抑制肽。在这里，LGH2 是一种新型 AMP，是从 HZ1 的基因组中鉴定出来的。总的来说，在 50%TFE 溶液中用 CD 测试时，LGH2 约有 52.76%呈α-螺旋，其余部分呈β-折叠和无规卷曲。该肽也是一种两亲性和阳离子分子，由 20 个氨基酸残基组成。LGH2 与 Temporin-RN3 的氨基酸序列相似度最高。然后，该肽成功地在 Rosetta(DE3)pLysS 中使用 SUMO 融合表达系统表达，并通过色谱技术进行纯化。肽的分子量为 2448 Da，通过 MALDI-TOF MS 确定。抗菌试验表明，该肽对 G+细菌具有很强的活性，特别是对 （MIC=4 μM）。溶血试验表明，该肽对绵羊红细胞的溶血活性较低。通过染料渗漏、CLSM、SEM 和 FCM 试验进一步研究了 LGH2 对病原体的抗菌机制。我们发现 LGH2 可以与细胞膜结合，并破坏其完整性。这些重要结果表明，LGH2 具有很大的潜力来治疗由 等病原菌引起的感染，为针对抗药性病原菌的抗菌肽提供了一个新的模板。
