Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Permoserstr. 15, 04318 Leipzig, Germany.
J Microbiol Methods. 2011 Aug;86(2):182-7. doi: 10.1016/j.mimet.2011.05.001. Epub 2011 May 9.
Fourier-transform infrared (FT-IR) spectroscopy is known as a high-resolution method for the rapid identification of pure cultures of microorganisms. Here, we evaluated FT-IR as a method for the quantification of bacterial populations in binary mixed cultures consisting of Pseudomonas putida and Rhodococcus ruber. A calibration procedure based on Principal Component Regression was developed for estimating the ratio of the bacterial species. Data for method calibration were gained from pure cultures and artificially assembled communities of known ratios of the two member populations. Moreover, to account for physiological variability, FT-IR measurements were performed with organisms sampled at different growth phases. Measurements and data analyses were subsequently applied to growing mixed cultures revealing that growth of R. ruber was almost completely suppressed in co-culture with P. putida. Population ratios obtained by fatty acid analysis as an independent reference method were in high agreement with the FT-IR derived ratios.
傅里叶变换红外（FT-IR）光谱学是一种快速鉴定纯培养微生物的高分辨率方法。在这里，我们评估了 FT-IR 作为一种定量分析由恶臭假单胞菌和红球菌组成的二元混合培养物中细菌种群的方法。建立了基于主成分回归的校准程序，用于估计细菌物种的比例。用于方法校准的数据来自纯培养物和已知两种成员种群比例的人工组装群落。此外，为了考虑生理变异性，用在不同生长阶段取样的生物体进行 FT-IR 测量。随后将测量和数据分析应用于生长的混合培养物，结果表明恶臭假单胞菌与红球菌共培养时，红球菌的生长几乎完全受到抑制。通过脂肪酸分析作为独立参考方法获得的种群比例与 FT-IR 衍生的比例高度一致。
