Heidrich Daiane, Koehler Alessandra, Ramírez-Castrillón Mauricio, Pagani Danielle Machado, Ferrão Marco Flores, Scroferneker Maria Lúcia, Corbellini Valeriano Antonio
Postgraduate Program in Medicine: Medical Sciences, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2400, CEP: 90035-003 Porto Alegre, RS, Brazil.
Postgraduate Program in Molecular and Cellular Biology, Biotechnology Center, Universidade Federal do Rio Grande do Sul, Avenida Bento Gonçalves, 9500, CEP: 91501-970 Porto Alegre, RS, Brazil.
Spectrochim Acta A Mol Biomol Spectrosc. 2021 Jun 5;254:119647. doi: 10.1016/j.saa.2021.119647. Epub 2021 Mar 10.
Chromoblastomycosis (CBM) is a skin and subcutaneous infection caused by species of seven fungal genera. Identification of CBM species is performed by DNA sequencing of one or more genes, which becomes a time-consuming work. Fourier Transform Infrared Spectroscopy (FTIR) has been used for the identification of other microorganisms, however, only one CBM genus was evaluated by FTIR analysis to date. Therefore, the study is aimed to differentiate the CBM agents for identification at genera level using FTIR supervised by Internal Transcribed Spacer (ITS) rDNA region. Seventy-seven isolates of the main five CBM genera were prepared for Attenuated Total Reflection FTIR (ATR-FTIR) with a new methodology using slices of dry fungus in glass fixing-modeling proposed in this study. The algorithm Hierarchical Cluster Analysis (HCA) was used to analyze the differences and similarities between species through the spectra. Orthogonal Partial Least Square Discriminant Analysis (OPLS-DA) allowed to correctly classify all samples of five CBM genera. The ATR-FTIR/OPLS-DA models highlighted important contributions of regions attributed to NH and OH stretching, amide I of proteins, polysaccharides bands and fingerprint region for the complete differentiation of the genera investigated. Thus, FTIR can be a fast and inexpensive alternative for identification of CBM agents.
着色芽生菌病（CBM）是一种由七个真菌属的物种引起的皮肤和皮下感染。CBM物种的鉴定通过对一个或多个基因进行DNA测序来完成，这是一项耗时的工作。傅里叶变换红外光谱（FTIR）已被用于其他微生物的鉴定，然而，迄今为止，通过FTIR分析仅评估了一个CBM属。因此，本研究旨在利用由内转录间隔区（ITS）rDNA区域监督的FTIR在属水平上区分用于鉴定的CBM病原体。本研究提出了一种新方法，使用玻璃固定模型中的干真菌切片，为主要五个CBM属的77个分离株制备衰减全反射FTIR（ATR-FTIR）。层次聚类分析（HCA）算法用于通过光谱分析物种之间的差异和相似性。正交偏最小二乘判别分析（OPLS-DA）能够正确地对五个CBM属的所有样本进行分类。ATR-FTIR/OPLS-DA模型突出了归因于NH和OH伸缩振动、蛋白质酰胺I、多糖带和指纹区的区域对所研究属的完全区分的重要贡献。因此，FTIR可以成为一种快速且廉价的鉴定CBM病原体的替代方法。
