Abstract：
Ergosterol is the key sterol component in the cell membrane of fungi including moulds and yeasts. Any decrease in the levels of ergosterol in the cell membrane of fungi render them venerable to cell membrane damage and even its death. Majority of antifungal drug targets the key enzymes involved in ergosterol biosynthesis pathway. The biochemical pathway for the synthesis of Ergosterol is a complex one, though the reactions carried by Squalene Epoxidase (SE) and 14α-demethylase (CYP51- a member of Cytochrome P450 family) serves to the key rate limiting reactions that can impact the overall production of Ergosterol. Allylamines class of antifungal drug target SE while Azoles target the CYP51. Currently advancement in the drug development is focused to introduce newer drugs that can simultaneously inhibit both this rate limiting enzymes. However, natural compounds established to possess antifungal activity but the major loophole about their understanding lies in the fact that their mode of action are severely unstudied. One such well-established antifungal natural phytochemical is Eugenol, and in current manuscript we investigated its efficacy to interact with both, SE and CYP51 of Candida albicans using molecular Docking, Free energy change calculations and Molecular Dynamics (MD) simulation, showing promising outcomes. For experimental studies, terbinafine, clotrimazole and eugenol showed 4 μg/ml, 2 μg/ml, and 512 μg/ml MIC90 values, respectively against C. albicans and also showed reduction in Ergosterol production at sub-MIC levels. The obtained result indicates the involvement of eugenol in the inhibition of enzymes require in the ergosterol biosynthesis pathway.
摘要：
麦角甾醇是真菌(包括霉菌和酵母)细胞膜中的关键甾醇组分。真菌细胞膜中麦角甾醇水平的任何降低都使其对细胞膜损伤甚至死亡具有重要意义。大多数抗真菌药物靶向麦角甾醇生物合成途径中涉及的关键酶。麦角甾醇合成的生化途径是复杂的,尽管角鲨烯环氧酶（SE）和14α-脱甲基酶（CYP51-细胞色素P450家族的成员）进行的反应是关键的限速反应，可以影响麦角甾醇的整体生产。抗真菌药物的烯丙胺类靶向SE，而唑类靶向CYP51。目前药物开发的进展集中于引入可以同时抑制这两种限速酶的更新药物。然而,天然化合物被确立为具有抗真菌活性，但关于它们理解的主要漏洞在于它们的作用模式尚未得到严格研究。一种这样成熟的抗真菌天然植物化学物质是丁香酚，在目前的手稿中，我们研究了它与两者相互作用的功效，使用分子对接的白色念珠菌SE和CYP51，自由能变化计算和分子动力学（MD）模拟，显示出有希望的结果。对于实验研究，特比萘芬,克霉唑和丁香酚显示4μg/ml，2μg/ml,和512μg/mlMIC90值，分别针对白色念珠菌，并且还显示出亚MIC水平的麦角甾醇产量减少。获得的结果表明丁香酚参与抑制麦角甾醇生物合成途径所需的酶。
