氮源影响PHB合成代谢的拉曼光谱分析  

Raman Spectral Profiles of PHB Synthesis Influenced by Different Nitrogen Sources

作　　者：覃赵军[1,2] 陶站华[1] 廖威[3] 陈真英[2] 黎永青 王桂文[1] 

机构地区：[1]广西科学院生物物理实验室,广西南宁530007 [2]广西大学行健文理学院,广西南宁530004 [3]广西职业技术学院食品与生物技术系,广西南宁530226 [4]美国东卡罗来那大学物理系,北卡罗来那州格林维尔nc27858

出　　处：《光学学报》2016年第4期217-225,共9页Acta Optica Sinica

基　　金：广西自然科学基金(2012GXNSFCA053001;2013GXNSFAA019043);广西高校自然科学基金(KY2015LX747)

摘　　要：应用拉曼光谱学结合奇异值分解方法在单细胞尺度上对杀虫贪铜菌(C.necator)H16菌株在不同的氮源下合成聚β-羟基丁酸(PHB)的代谢动态进行分析。结果显示,硫酸铵是PHB发酵的理想氮源,对应PHB发酵速度、效率和产量在测试氮源中表现最好。奇异值分解结果显示,源自RNA、DNA、蛋白质和PHB的拉曼峰是发酵的主要特征,随着发酵进程的延伸,菌体细胞差异、产物含量差别逐渐增大。分析PHB产物快速合成过程,可见表征核酸、蛋白质和PHB的782、1574、1660、1732 cm^(-1)等峰的强度变化活跃;不同氮源下,782 cm^(-1)峰与1660 cm^(-1)峰的强度呈正相关,而1660 cm^(-1)峰与1732 cm^(-1)峰的强度呈负相关。因此,不同氮源可能影响细胞的RNA代谢和蛋白质代谢,从而间接影响PHB的合成。拉曼光谱结合数据挖掘技术可以分析微生物发酵过程中的代谢信息,从分子光谱的角度为寻找最佳的发酵条件提供新的信息。Laser tweezers Raman spectroscopy and singular value decomposition are used to explore the synthesis dynamics of biodegradable plastic poly- β-hydroxybutyrate（PHB） in C. necator H16 strain cultured with different nitrogen sources at the single- cell level. The results show that ammonium sulfate performing best on fermentation speed, efficiency and productivity in all tested nitrogen sources, is demonstrated as an ideal nitrogen source for PHB fermentation. The singular value decomposition results reveal that the main fermentation features are the Raman peaks belonging to RNA, DNA, protein and PHB, and the difference in bacterial cells and product yield becomes more notable as the fermentation process works. The dynamics of Raman intensity peaks of nucleic acid, protein and PHB at 782, 1574, 1660, 1732 cm^（-1）are active to the fast PHB synthesis, and no matter what nitrogen sources are used, the intensity of peaks at 1660 cm^（-1）and 782 cm^（-1）is positively correlated, but the intensity of 1660 cm^（-1）and 1732 cm^（-1）peaks is negatively correlated. The results suggest that nitrogen sources influence the RNA and the protein metabolism and then affect the synthesis of PHB indirectly. Raman spectroscopy combining with data analysis can provide the metabolism information of the microbial fermentation and offer a powerful experiment basis for optimizing fermentation process.

关 键 词：生物光学 拉曼光谱 奇异值分解 氮源 聚Β-羟基丁酸 单细胞分析 

分 类 号：O657.37[理学—分析化学]