采用傅里叶变换红外光谱非破坏性地分析了蜡样芽孢杆菌,在获得完整全细胞组分的红外光谱信息基础上,进行了二阶导数光谱转换。结果表明,根据二阶导数光谱特征吸收峰可区分蜡样芽孢杆菌细胞的荚膜、芽孢、贮能物质等特殊结果物质。以1654cm^-1附近的α-螺旋结构的蛋白酰胺带吸收峰与在1601和1403cm^-1附近显示的强羧基伸缩振动吸收峰可探测到细胞荚膜结构;根据1617,1372和1569cm^-1附近的吡啶二羧酸(DPA)的吸收峰可认定细胞内芽孢的存在;此外,可在二阶导数红外谱图中同时找到多聚β-羟基丁酸(PHB)细胞粒、荚膜、芽孢的吸收峰。由二阶导数红外光谱可分辨重叠光谱来探测细胞多种结构物质,为从分子生物学与细胞生物学角度,为研究蜡样芽孢杆菌提供参考信息。
Some particular cell components of intact Bacillus cereus could be detected and identified by Fourier transform infrared spectroscopy (FTIR). FTIR were collected directly, then the FTIR spectra of the samples were converted into second derivative spectra. Typical marker bands were used to identify these bacterial cell components such as capsules, endospores or storage materials. Capsules were detected in cell by a strong amide band near 1 654 cm^-1 typical for a-helical structures and by strong carboxylate stretching vibrations(≈ 1 601 cm^-1 and ≈ 1 403 cm^-1 , respectively). The formation of endospores was discovered using marker bands for dipicolinic acid (located at ≈1 617 cm^-1, ≈1 372 cm^-1 and ≈1 569 cm^-1 ). Spectra of this strain showed expression of poly-β-hydroxybutyric acid granules, capsules and endospores simultaneously. These bacterial cell components can be identified by second derivative FTIR spectroscopy which can distinguish the overlap spectrum. And that offered some referenced information for molecular biology and cellular biology.