Biswas Priyam, Bose Soham, Chakraborty Sudipta
Department of Biochemistry, University of Calcutta, Kolkata, West Bengal, 700 019, India.
Department of Microbiology, Government General Degree College, Narayangarh, Rathipur, Narayangarh, Midnapore, West Bengal, 721437, India.
World J Microbiol Biotechnol. 2025 Mar 13;41(3):104. doi: 10.1007/s11274-025-04304-y.
Biofilm formed by Pseudomonas aeruginosa is a three dimensional microbial matrix that confers multidrug resistance properties along with the proficiency to evade the host immune system. The present study aims to determine the combinatorial effects of vitamin D3 (cholecalciferol) with two already reported antibiofilm agents: streptomycin and thymoquinone separately against P. aeruginosa biofilms. The minimum inhibitory concentration of streptomycin, thymoquinone and D3 was found to be 20, 10 and 100 μg/mL respectively. The inhibition of biofilm formation and pre-formed biofilm disintegration properties of streptomycin and thymoquinone alone or in combination with D3 at their sub-MIC concentration was determined by crystal violet staining and confocal laser scanning microscopy. A significant inhibition of metabolic activities like oxygen consumption rate and reduction in quorum sensing related cellular activities like swarming motilities, pyocyanin production and extracellular protease secretion by P. aeruginosa were also observed as a result of this combinatorial effect. Both of these combinatorial applications were found to accumulate ROS in bacterial cells, which has been proved to be one of the main causes of their antibiofilm activity. Effect of these two drug combinations on bacterial lettuce leaf infection was also evaluated. Molecular docking analysis indicated that thymoquinone combined D3 can interact more efficiently with the quorum sensing proteins LasI and LasR. The host cell cytotoxicity of these two combinations was found to be negligible on the murine macrophage cell line. These findings suggest that D3 potentiates the antimicrobial and antibiofilm efficacy of both streptomycin and thymoquinone against P. aeruginosa. Although both combinations have shown significant antibiofilm and antimicrobial potential, combinatorial performances of D3 combined thymoquinone were found to be more promising.
铜绿假单胞菌形成的生物膜是一种三维微生物基质，具有多重耐药特性，并能逃避宿主免疫系统。本研究旨在确定维生素D3（胆钙化醇）与两种已报道的抗生物膜药物：链霉素和百里醌分别对铜绿假单胞菌生物膜的联合作用。链霉素、百里醌和D3的最低抑菌浓度分别为20、10和100μg/mL。通过结晶紫染色和共聚焦激光扫描显微镜测定链霉素和百里醌单独或与D3在其亚抑菌浓度下对生物膜形成的抑制作用和对预形成生物膜的分解特性。由于这种联合作用，还观察到铜绿假单胞菌的代谢活性如氧消耗率受到显著抑制，以及群体感应相关细胞活性如群体运动、绿脓菌素产生和细胞外蛋白酶分泌减少。发现这两种联合应用都能在细菌细胞中积累活性氧，这已被证明是它们抗生物膜活性的主要原因之一。还评估了这两种药物组合对生菜叶片细菌感染的影响。分子对接分析表明，百里醌联合D3能更有效地与群体感应蛋白LasI和LasR相互作用。发现这两种组合对小鼠巨噬细胞系的宿主细胞细胞毒性可忽略不计。这些发现表明，D3增强了链霉素和百里醌对铜绿假单胞菌的抗菌和抗生物膜功效。虽然两种组合都显示出显著的抗生物膜和抗菌潜力，但发现D3联合百里醌的联合性能更有前景。
