Amity Institute of Biotechnology, Amity University Rajasthan, Jaipur, India.
Department of Biotechnology, Maharani Lakshmi Ammanni College for Women, Bangalore, India.
Protein Pept Lett. 2020;27(7):582-592. doi: 10.2174/0929866527666191227143048.
Enterococcus faecalis (Ef) infections are becoming dreadfully common in hospital environments. Infections caused by Ef are difficult to treat because of its acquired resistance to different class of antibiotics, making it a multidrug resistant bacteria. Key pathogenic factor of Ef includes its ability to form biofilm on the surface of diagnostic and other medical devices. Sortase A (SrtA) is a cysteine transpeptidase which plays a pivotal role in the formation of biofilm in Ef, hence, it is considered as an important enzyme for the pathogenesis of Ef. Thus, inhibition of (SrtA) will affect biofilm formation, which will reduce its virulence and eventually Ef infection will be abridged.
To find potential inhibitors of Enterococcus faecalis Sortase A (EfSrtA) through insilico and in-vitro methods.
Gene coding for EfSrtA was cloned, expressed and purified. Three-dimensional model of EfSrtA was created using Swiss-Model workspace. In-silico docking studies using Autodock vina and molecular dynamics simulations of the modelled structures using Gromacs platform were performed to explore potential lead compounds against EfSrtA. In-vitro binding experiments using spectrofluorometric technique was carried out to confirm and validate the study.
In-silico docking and in-vitro binding experiments revealed that curcumin, berberine and myricetin bound to EfSrtA at nanomolar concentrations with high affinity.
This is a first structural report of EfSrtA with curcumin, berberine and myricetin. Taking in account the herbal nature of these compounds, the use of these compounds as inhibitors will be advantageous. This study validated curcumin, berberine and myricetin as potential inhibitors of EfSrtA.
粪肠球菌（Ef）感染在医院环境中变得越来越普遍。由于 Ef 对不同类别的抗生素产生了获得性耐药性，因此其引起的感染难以治疗，使其成为一种多药耐药菌。Ef 的关键致病因素包括其在诊断和其他医疗设备表面形成生物膜的能力。天冬酰胺酰基转移酶 A（SrtA）是一种半胱氨酸转肽酶，在 Ef 生物膜形成中起着关键作用，因此，它被认为是 Ef 发病机制的重要酶。因此，（SrtA）的抑制将影响生物膜的形成，从而降低其毒力，最终 Ef 感染将得到缩短。
通过计算机模拟和体外方法寻找粪肠球菌天冬酰胺酰基转移酶 A（EfSrtA）的潜在抑制剂。
克隆、表达和纯化 EfSrtA 的编码基因。使用 Swiss-Model 工作区创建 EfSrtA 的三维模型。使用 Autodock vina 进行计算机模拟对接研究，并使用 Gromacs 平台对模型结构进行分子动力学模拟，以探索针对 EfSrtA 的潜在先导化合物。使用荧光光谱技术进行体外结合实验，以确认和验证研究结果。
计算机模拟对接和体外结合实验表明，姜黄素、小檗碱和杨梅素以纳摩尔浓度与 EfSrtA 结合，具有高亲和力。
这是 EfSrtA 与姜黄素、小檗碱和杨梅素的首次结构报告。考虑到这些化合物的草药性质，这些化合物作为抑制剂的使用将具有优势。本研究验证了姜黄素、小檗碱和杨梅素是 EfSrtA 的潜在抑制剂。
