Jhaveri Microbiology Centre, Prof. Brien Holden Eye Research Centre, L. V. Prasad Eye Institute, Kallam Anji Reddy Campus, Hyderabad, Telangana, 500034, India.
Sci Rep. 2022 Jul 8;12(1):11606. doi: 10.1038/s41598-022-15809-z.
Microbes residing in biofilms confer several fold higher antimicrobial resistances than their planktonic counterparts. Compared to monomicrobial biofilms, polymicrobial biofilms involving multiple bacteria, multiple fungi or both are more dominant in nature. Paradoxically, polymicrobial biofilms are less studied. In this study, ocular isolates of Staphylococcus aureus, S. epidermidis and Candida albicans, the etiological agents of several ocular infections, were used to demonstrate their potential to form mono- and polymicrobial biofilms both in vitro and on human cadaveric corneas. Quantitative (crystal violet and XTT methods) and qualitative (confocal and scanning electron microscopy) methods demonstrated that they form polymicrobial biofilms. The extent of biofilm formation was dependent on whether bacteria and fungi were incubated simultaneously or added to a preformed biofilm. Additionally, the polymicrobial biofilms exhibited increased resistance to different antimicrobials compared to planktonic cells. When the MBECs of different antibacterial and antifungal agents were monitored it was observed that the MBECs in the polymicrobial biofilms was either identical or decreased compared to the monomicrobial biofilms. The results are relevant in planning treatment strategies for the eye. This study demonstrates that ocular bacteria and fungi form polymicrobial biofilms and exhibit increase in antimicrobial resistance compared to the planktonic cells.
与浮游生物相比，生活在生物膜中的微生物具有高出数倍的抗微生物耐药性。与单微生物生物膜相比，涉及多种细菌、多种真菌或两者兼有的多微生物生物膜在自然界中更为普遍。矛盾的是，多微生物生物膜的研究较少。在这项研究中，我们使用眼部分离的金黄色葡萄球菌、表皮葡萄球菌和白色念珠菌（几种眼部感染的病原体）来证明它们在体外和人尸体角膜上形成单微生物和多微生物生物膜的潜力。定量（结晶紫和 XTT 方法）和定性（共聚焦和扫描电子显微镜）方法证明它们形成了多微生物生物膜。生物膜形成的程度取决于细菌和真菌是同时孵育还是添加到已形成的生物膜中。此外，与浮游细胞相比，多微生物生物膜表现出对不同抗菌药物的耐药性增加。当监测不同抗菌和抗真菌药物的 MBEC 时，观察到多微生物生物膜中的 MBEC 与单微生物生物膜相同或降低。这些结果与眼部治疗策略的规划有关。本研究表明，眼部细菌和真菌形成多微生物生物膜，并表现出比浮游细胞更高的抗微生物耐药性。
