Dutta Bandita, Basu Debarati, Lahiri Dibyajit, Nag Moupriya, Ray Rina Rani
Department of Biotechnology, Maulana Abul Kalam Azad University of Technology, Nadia, West Bengal, India.
Department of Biotechnology, University of Engineering and Management, Kolkata, India.
Naunyn Schmiedebergs Arch Pharmacol. 2025 Mar;398(3):2983-2999. doi: 10.1007/s00210-024-03458-0. Epub 2024 Sep 23.
A large number of recalcitrant bacterial pathogens cannot be easily treated by antibiotics due to the existence of biofilm. Hence, an alternative strategy needs to be adopted to remove the biofilm without the development of antibiotic resistance. Bacteriocins, ribosome-mediated proteinaceous toxins, having potential to inhibit the growth of closely or distantly related bacteria. In the present study, after screening a number of sources, a bacteriocin-producing strain, Enterococcus faecalis BDR22, was isolated that showed a significant reduction in the growth of planktonic cells of Gram-positive Staphylococcus aureus, Bacillus subtilis, and Gram-negative Pseudomonas aeruginosa, Escherichia coli, Serratia marcescens, Enterobacter cloacae, and Klebsiella pneumoniae compared to the conventional antibiotic tetracycline. The considerable reduction of the biofilm-forming sessile cells of the test organisms S. aureus (ATCC 23235) and P. aeruginosa (ATCC 10145), with no significant cell revival even after withdrawal of the treatment, was also observed. The extracellular polymeric substance (EPS) content of the biofilm was also reduced, with around 84% total carbohydrate reduction found for both microorganisms. The antibiofilm activities of the strain against test organisms were clearly visible from scanning electron micrographs and confirmed by the changes in functional groups (C-H, -OH, C = C, C-N etc.) of biofilm matrices by Fourier transform infrared spectroscopy (FTIR) analysis. The molecular docking interactions with docking energies ∆G of - 54.40 kcal/mol and - 66.2373 kcal/mol validate the affinity of the bacteriocin towards the biofilm-forming protein, which confirms the competence of the bacteriocin-producing strain to act as an effective antimicrobial and antibiofilm agent, replacing antibiotics.
由于生物膜的存在,大量顽固的细菌病原体难以用抗生素轻易治疗。因此,需要采用一种替代策略来去除生物膜,同时又不产生抗生素耐药性。细菌素是核糖体介导的蛋白质毒素,具有抑制亲缘关系近或远的细菌生长的潜力。在本研究中,经过对多个来源的筛选,分离出一株产细菌素的粪肠球菌BDR22,与传统抗生素四环素相比,该菌株对革兰氏阳性的金黄色葡萄球菌、枯草芽孢杆菌以及革兰氏阴性的铜绿假单胞菌、大肠杆菌、粘质沙雷氏菌、阴沟肠杆菌和肺炎克雷伯菌的浮游细胞生长有显著抑制作用。还观察到受试生物金黄色葡萄球菌(ATCC 23235)和铜绿假单胞菌(ATCC 10145)形成生物膜的固着细胞数量大幅减少,即使在停止处理后细胞也没有明显复苏。生物膜的胞外聚合物(EPS)含量也有所降低,两种微生物的总碳水化合物含量均减少了约84%。通过扫描电子显微镜照片可以清楚地看到该菌株对受试生物的抗生物膜活性,傅里叶变换红外光谱(FTIR)分析生物膜基质的官能团(C-H、-OH)、C = C、C-N等)变化也证实了这一点。与对接能量∆G为-54.40千卡/摩尔和-66.2373千卡/摩尔的分子对接相互作用验证了细菌素对生物膜形成蛋白的亲和力,这证实了产细菌素菌株作为一种有效的抗菌和抗生物膜剂替代抗生素的能力。