Culha Mustafa, Adigüzel Ahmet, Yazici M Müge, Kahraman Mehmet, Sahin Fikrettin, Güllüce Medine
Yeditepe University, Faculty of Engineering and Architecture, Genetics and Bioengineering Department, Kayisdagi, 34755, Istanbul, Turkey.
Appl Spectrosc. 2008 Nov;62(11):1226-32. doi: 10.1366/000370208786401545.
Surface-enhanced Raman scattering (SERS) can provide molecular-level information about the molecules and molecular structures in the vicinity of nanostructured noble metal surfaces such as gold and silver. The three thermophilic bacteria Bacillus licheniformis, Geobacillus stearothermophilus, and Geobacillus pallidus, a Gram-negative bacterium E. coli, and a Gram-positive bacterium B. megaterium are comparatively characterized using SERS. The SERS spectra of thermophilic bacteria are similar, while they show significant differences compared to E. coli and B. megaterium. The findings indicate that a higher number of thiol residues and possible S-S bridges are present in the cell wall structure of thermophilic bacteria, providing their stability at elevated temperatures. Incubating the thermophilic bacteria with colloidal silver suspension at longer times improved the bacteria-silver nanoparticle interaction kinetics, while increased temperature does not have a pronounced effect on spectral features. A tentative assignment of the SERS bands was attempted for thermophilic bacteria. The results indicate that SERS can be a useful tool to study bacterial cell wall molecular differences.
表面增强拉曼散射（SERS）能够提供有关纳米结构贵金属表面（如金和银）附近分子及分子结构的分子水平信息。利用SERS对三种嗜热细菌地衣芽孢杆菌、嗜热栖热放线菌和苍白嗜热放线菌、一种革兰氏阴性菌大肠杆菌以及一种革兰氏阳性菌巨大芽孢杆菌进行了比较表征。嗜热细菌的SERS光谱相似，但与大肠杆菌和巨大芽孢杆菌相比显示出显著差异。研究结果表明，嗜热细菌细胞壁结构中存在更多的硫醇残基和可能的S-S桥，这为它们在高温下提供了稳定性。将嗜热细菌与胶体银悬浮液长时间孵育可改善细菌与银纳米颗粒的相互作用动力学，而升高温度对光谱特征没有显著影响。尝试对嗜热细菌的SERS谱带进行初步归属。结果表明，SERS可作为研究细菌细胞壁分子差异的有用工具。
