Faculty of Medicine of the Federal University of Uberlândia (FAMED-UFU), Uberlândia, Brazil.
Technical Health School of the Federal University of Uberlândia (ESTES-UFU), Uberlândia, Brazil.
J Appl Microbiol. 2021 Oct;131(4):2049-2060. doi: 10.1111/jam.15066. Epub 2021 Mar 23.
The aim of this study was to evaluate the formation of biofilm by Candida spp. isolated from the bloodstream, using traditional spectrophotometric methodologies. In addition, the goal was to compare the results with those obtained through MALDI-TOF/MS, as well as to verify its use as a potential tool for the detection of biofilm-forming strains.
Hundred and thirteen isolates of Candida spp. were studied: 41 were Candida albicans, 27 C. tropicalis, 18 C. glabrata, 17 C. parapsilosis and 10 C. krusei. Metabolic activity was determined through the tetrazolium salt (XTT) reduction assay and biomass by staining with Crystal Violet. All isolates were able to form biofilm, 94% of which were strong producers, with high biomass quantification (95%; 107/113) and high metabolic activity (99%; 112/113). Mass spectra of the biofilm-producing isolates showed differences in the intensity of mass peaks when compared with the spectra of the nonproducing strains.
It was demonstrated that MALDI-TOF/MS was able to detect specific biofilm proteins, as the mass spectra of the isolates presented differences when compared with nonproducing strains.
MALDI-TOF/MS can become a valuable tool for biofilm detection at the moment of the identification of the microorganism, thus contributing greatly to the management of patients with Candidemia.
本研究旨在使用传统分光光度法评估从血流中分离的念珠菌属生物膜的形成。此外，还旨在将结果与 MALDI-TOF/MS 获得的结果进行比较，并验证其作为检测生物膜形成菌株的潜在工具的用途。
研究了 113 株念珠菌属分离株：41 株为白色念珠菌，27 株为热带念珠菌，18 株为光滑念珠菌，17 株为近平滑念珠菌，10 株为克柔念珠菌。代谢活性通过四唑盐（XTT）还原测定法确定，生物量通过结晶紫染色确定。所有分离株均能形成生物膜，其中 94%为强产生者，具有高生物量定量（95%；107/113）和高代谢活性（99%；112/113）。产生物膜分离株的质谱显示与非产生产物膜的菌株相比，质量峰的强度存在差异。
证明 MALDI-TOF/MS 能够检测特定的生物膜蛋白，因为与非产生产物膜的菌株相比，分离株的质谱存在差异。
MALDI-TOF/MS 可以成为鉴定微生物时检测生物膜的有价值工具，从而极大地有助于管理念珠菌血症患者。
