以2株拉格型啤酒酵母菌株为研究对象，通过研究其在传代及自溶过程中细胞形态、细胞活性活力、胞内活性氧(reactive oxygen species，ROS)以及DNA的损伤等指标，分析啤酒酵母在传代发酵及自溶过程中的生理性能变化。结果表明，在传代培养过程中，原本表面圆润饱满且呈椭圆型的啤酒酵母细胞会在活力下降后出现褶皱，甚至因为细胞内部结构的严重水解而干瘪失型。同时，细胞壁厚度在传代过程中也会逐渐变薄；高活力的菌株所表现的抗自溶能力、抗压能力都强于活力低的菌株，而且高活力的菌株所产生的ROS含量相对少、且稳定，DNA损伤速度也相对缓慢。研究啤酒酵母在传代及自溶过程中具体的生理性能变化，不仅有助于了解酵母细胞在传代发酵过程中的自我防御机制，对选育优良啤酒酵母也有重要指导意义。

Two lager yeast strains were used to study the cell morphology, cell viability and vitality, reactive oxygen species (ROS) and DNA damage so as to analyze the changes of physiological properties of lager yeasts during serial re-pitching and autolysis. The results showed that, lager yeast cells with full and round surface and plump shape became wrinkled during serial re-pitching, and even withered out because of the severe hydrolysis of the inner structure of cells. At the same time, the thickness of cell wall gradually became thinner during serial re-pitching, which affected the morphology of the cells. Lager yeast with better anti-autolytic ability showed higher vitality, better stress resistance, lower ROS accumulation, and less DNA damage. Therefore, it is of great significance to understand the physiological changes and autolysis performances of lager yeast during serial re-pitching, which will helpful for understanding the self-defense mechanism of yeast cells during serial re-pitching. In the meantime, the findings from this study has important guiding significance for breeding of brewer's yeasts.