School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China; Department of Pharmacy, Guizhou Provincial People's Hospital, Guiyang, Guizhou, China.
School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China.
Int J Med Microbiol. 2020 Jul;310(5):151435. doi: 10.1016/j.ijmm.2020.151435. Epub 2020 Jun 3.
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the important causes of food poisoning and infectious diseases worldwide, it can produce a large number of virulence factors, enhance the colonization ability of the host so that it can quickly colonize and spread on the surface of the objects. Essential oil (EO) is one of the natural products with antimicrobial properties, can be used as an important source of antibacterial agent discovery, and has a broad development prospect. However, the unclear mechanisms of antibacterial action have become an obstacle to its further development and use. Hence, the objective of the present study was to reveal the antibacterial mechanism of EO from Amomum villosum Lour (A villosum Lour) against MRSA using label-free quantitative proteomics, investigate the effect of EO on the bacterial proteome, enzymatic activities and leakage of bacterial intracellular biomacromolecule. Proteomic analysis of MRSA in the presence of EO found that a total of 144 differential expressed proteins (DEPs) between the control and treatment group, in which 42 proteins were distinctly up-regulated and 102 proteins were down-regulated. Besides, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, determination of cell membrane permeability and apoptosis, scanning electron microscopy (SEM) observations, bacterial surface hydrophobicity, and biofilm formation measurement were performed. Collectively, the above results indicated that the cell membrane damage by EO leads to the loss of membrane integrity and causes leakage of intracellular macromolecular substances, inhibition of protein, and biofilm synthesis. These findings manifested that EO exerts antibacterial effect by multiple avenues and expands our understanding of the antibacterial mechanism, it has potential application value in food preservative and pharmaceutical industries.
耐甲氧西林金黄色葡萄球菌（MRSA）是世界范围内引起食物中毒和传染病的重要原因之一，它可以产生大量的毒力因子，增强宿主的定植能力，使其能够快速定植和在物体表面传播。精油（EO）是具有抗菌特性的天然产物之一，可用作抗菌剂发现的重要来源，具有广阔的发展前景。然而，抗菌作用的机制尚不清楚，成为其进一步发展和应用的障碍。因此，本研究旨在采用无标记定量蛋白质组学揭示 Amomum villosum Lour（A villosum Lour）精油对 MRSA 的抗菌机制，研究精油对细菌蛋白质组、酶活性和细菌胞内生物大分子泄漏的影响。在存在精油的情况下对 MRSA 进行蛋白质组分析，发现对照组和处理组之间有 144 个差异表达蛋白（DEPs），其中 42 个蛋白明显上调，102 个蛋白下调。此外，还进行了十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）分析、细胞膜通透性和凋亡测定、扫描电子显微镜（SEM）观察、细菌表面疏水性和生物膜形成测定。综上所述，这些结果表明，精油通过多种途径破坏细胞膜，导致膜完整性丧失，导致细胞内大分子物质泄漏、蛋白质抑制和生物膜合成。这些发现表明，精油通过多种途径发挥抗菌作用，扩展了我们对其抗菌机制的认识，在食品防腐剂和制药行业具有潜在的应用价值。
