[Second derivative FTIR spectroscopic study of Bacillus cereus].

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 1654 cm(-1) typical for alpha-helical structures and by strong carboxylate stretching vibrations (approximately 1601 cm(-1) and approximately 1403 cm(-1), respectively). The formation of endospores was discovered using marker bands for dipicolinic acid (located at approximately 1617 cm(-1), approximately 1372 cm(-1) and approximately 1569 cm(-1)). Spectra of this strain showed expression of poly-beta-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.