Molecular Microbiology Lab, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, India.
J Appl Microbiol. 2010 Jul;109(1):128-36. doi: 10.1111/j.1365-2672.2009.04634.x. Epub 2009 Nov 23.
The major objective of the study was to analyse exopolysaccharide produced by a biofilm forming-clinical strain of Candida albicans.
The biofilm-forming ability of C. albicans recovered from infected intrauterine devices (IUDs) was evaluated using XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide) reduction assay. The morphological characteristics of the biofilm were assessed using scanning electron microscopy (SEM), atomic force microscopy (AFM) and confocal laser scanning microscopy (CLSM). Biochemical characterization of the exopolysaccharide was carried out by gel permeation chromatography, gas chromatography (GC), Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. Microscopic studies of C. albicans biofilm revealed complex, heterogeneous three-dimensional structure, in which yeast cells and hyphal elements were entrenched within exopolysaccharides matrix. Chromatographic analysis data indicated C. albicans exopolysaccharide (c. 300 kDa) to be made up of four major sugar units. The FTIR spectrum revealed specific absorbance of O-H, C-H, O=C=O, C=O, C-N and C-C ring stretching. (1) H and (13) C NMR data showed the presence of β (1→6) and β (1→3) linkages in the exopolysaccharide chain that were assigned to α-D-glucose and β-D-glucose, α-D-mannose, α-L-rhamnose and N-acetyl glucosamine (β-D-GlcNAc), respectively.
Study suggested the production of a water soluble c. 300 kDa exopolysaccharide by C. albicans made up of glucose, mannose, rhamnose and N-acetyl glucosamine subunits.
The study could assist in the development of novel therapeutics aimed at disrupting C. albicans biofilms that will translate into improved clearance of Candida-related infections.
本研究的主要目的是分析生物膜形成的临床白色念珠菌菌株产生的胞外多糖。
使用 XTT（2,3-双[2-甲氧基-4-硝基-5-磺苯基]-2H-四唑-5-羧酰胺）还原测定法评估从感染宫内节育器（IUD）中回收的白色念珠菌的生物膜形成能力。使用扫描电子显微镜（SEM）、原子力显微镜（AFM）和共聚焦激光扫描显微镜（CLSM）评估生物膜的形态特征。通过凝胶渗透色谱、气相色谱（GC）、傅里叶变换红外（FTIR）光谱和核磁共振（NMR）光谱对胞外多糖进行生化特性分析。白色念珠菌生物膜的显微镜研究显示出复杂的、不均匀的三维结构，其中酵母细胞和菌丝体被嵌入胞外多糖基质中。色谱分析数据表明，白色念珠菌胞外多糖（约 300 kDa）由四个主要糖单元组成。FTIR 光谱显示 O-H、C-H、O=C=O、C=O、C-N 和 C-C 环伸展的特定吸收。（1）H 和（13）C NMR 数据显示，胞外多糖链中存在β（1→6）和β（1→3）键，分别被分配给α-D-葡萄糖和β-D-葡萄糖、α-D-甘露糖、α-L-鼠李糖和 N-乙酰葡萄糖胺（β-D-GlcNAc）。
研究表明，白色念珠菌产生一种水溶性约 300 kDa 的胞外多糖，由葡萄糖、甘露糖、鼠李糖和 N-乙酰葡萄糖胺亚基组成。
该研究可协助开发旨在破坏白色念珠菌生物膜的新型疗法，从而改善清除与念珠菌相关的感染。
