一种酵母细胞生长现象的实时单细胞拉曼光谱观察

用拉曼镊子观察单个即发活性干酵母(Saccharomy cescerevisiae)细胞在2.0%葡萄糖溶液中的活化过程,收集其拉曼光谱。结果发现,在某一批次的产品中,酵母细胞的1364cm-1峰强度随着细胞的活化而显著增加,531cm-1、652cm-1、1053cm-1等源自葡萄糖或葡萄糖基的信号峰也会随细胞的生长而增强,随后增强的还有1432cm-1、1448cm-1、1561cm-1等源自脂类物质的峰,而源自蛋白质及脂类的1000cm-1、1445cm-1、1655cm-1等峰的信号强度基本不变,酵母细胞代谢活跃的标志峰1603cm-1也基本不变。该批次产品中,10次实验有7次观察到上述现象,而在别的批次产品中并没有观察到该现象。用单细胞拉曼光谱实时记录了这一特殊的生长现象。

Real-time Raman Spectrum of a Phenomenon in the Activation Process of Single Yeast Cell Cultured in Glucose Solution

Raman tweezers,a novel technique that combines Raman spectroscopy with optical tweezers,has the potential to become an effective tool for analysis single cell suspended in solution.To real-time investigate the biochemical proceedings in single cell,a Raman tweezers setup was used to trap a single instant active dry yeast cell and to acquire the real-time Raman spectrum of the trapping cell from dormancy to activation cultured in 2.0%(W/V)glucose.During the activating process,the intensity of bands derived from protein or lipids,such as 1000 cm-1,1445 cm-1,1655 cm-1,were not changed evidently.The intensity of the 1603 cm-1 band,which was considered as the signature of metabolic activity,was not changed evidently too.But the bands at 531cm-1,652cm-1,1053cm-1,1364 cm-1,which were assigned to trehalose,or glucose-base carbohydrates,were increased as the cell grew.This phenomenon,occurred in seven individual experiments of ten repeats using a batch of instant active yeast cells as tested cells,but did not occur when other batches of instant active yeast cells were tested.This peculiar process of adaptation was recorded by real-time Raman spectrum and the result indicates Raman tweezers is an effective tool for single-cell analysis.