Ramos Lívia S, Mello Thaís P, Branquinha Marta H, Santos André L S
Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21941-901, Brazil.
Programa de Pós-Graduação em Bioquímica (PPGBq), Instituto de Química (IQ), UFRJ, Rio de Janeiro 21941-909, Brazil.
J Fungi (Basel). 2020 Apr 3;6(2):46. doi: 10.3390/jof6020046.
species complex (, , and var. ) has emerged as opportunistic, multidrug-resistant yeasts able to cause fungemia. Previously, we showed that complex formed biofilm on polystyrene. Biofilm is a well-known virulence attribute of spp. directly associated with drug resistance. In the present study, the architecture and the main extracellular matrix (ECM) components forming the biofilm over polystyrene were investigated in clinical isolates of the complex. We also evaluated the ability of these fungi to form biofilm on catheters used in medical arena. The results revealed that all fungi formed biofilms on polystyrene after 48 h at 37 °C. Microscopic analyses demonstrated a dense network of yeasts forming the biofilm structure, with water channels and ECM. Regarding ECM, proteins and carbohydrates were the main components, followed by nucleic acids and sterols. Mature biofilms were also detected on late bladder (siliconized latex), nasoenteric (polyurethane), and nasogastric (polyvinyl chloride) catheters, with the biomasses being significantly greater than on polystyrene. Collectively, our results demonstrated the ability of the species complex to form biofilm on different types of inert surfaces, which is an incontestable virulence attribute associated with devices-related candidemia in hospitalized individuals.
种复合体（、和变种）已成为能够引起真菌血症的机会性、多重耐药酵母。此前，我们发现种复合体在聚苯乙烯上形成生物膜。生物膜是白色念珠菌属众所周知的毒力属性，与耐药性直接相关。在本研究中，我们对种复合体的临床分离株在聚苯乙烯上形成生物膜的结构和主要细胞外基质（ECM）成分进行了研究。我们还评估了这些真菌在医疗领域使用的导管上形成生物膜的能力。结果显示，所有真菌在37℃下培养48小时后均在聚苯乙烯上形成了生物膜。显微镜分析表明，形成生物膜结构的酵母形成了密集的网络，伴有水通道和ECM。关于ECM，蛋白质和碳水化合物是主要成分，其次是核酸和甾醇。在晚期膀胱（硅化乳胶）、鼻肠（聚氨酯）和鼻胃（聚氯乙烯）导管上也检测到了成熟的生物膜，其生物量明显大于在聚苯乙烯上的生物量。总体而言，我们的结果证明了种复合体在不同类型惰性表面上形成生物膜的能力，这是与住院个体中与器械相关的念珠菌血症相关的无可争议的毒力属性。
