合成生物学中的细菌细胞周期 Understanding bacterial cell cycle using synthetic biology

Views:2945       Publish Time: 2019-03-02

       合成生物学致力于根据人类的需求对现有的生物系统进行重新设计和改造或设计和构建自然界不存在的生物原件和生物系统。相关理性设计能力的欠缺在很大程度上限制了合成生物学的发展，深入了解已有生命形式的运行机制对突破上述瓶颈有着积极的作用。

       倍增是所有生命形式得以传递延续的内在需求。就细菌细胞而言，在不同的生长环境中，其倍增时间各异，既可以在大约20分钟内完成细胞的倍增，也可能需要数小时才能完成细胞的倍增。在不同倍增时间的情况下，细胞的大小、细胞内DNA含量多少、起始DNA复制的时间点、DNA复制速率各不相同。深入理解细菌细胞这一相对简单的生命形式的DNA复制及细胞分裂的调控机制属于微生物生理学的重要研究内容，相关的研究有助于提升人们在合成生物学研究过程中的设计能力。

       本研究方向将结合合成生物学与显微观测、流式细胞分析等单细胞水平的研究方法和经典生化分析、转录组分析、蛋白质组分析等群体水平的研究手段，定量的阐明细菌细胞生长、DNA复制及细胞分裂之间的内在联系的并对相应的分子调控机制进行深入的探讨。

Synthetic biology aims to redesign and reconstruct existing living systems or design and create biological parts/systems that do not exist in nature. The lack of capabilities in rational design has largely limited the advancement of synthetic biology, and a deeper understanding of the workings of existing life forms will greatly help us to overcome this bottleneck.

Multiplication is a fundamental requirement for all life forms. The doubling time of bacterial cells varies in different growth environments, ranging from approximately 20 minutes to several hours. The cell size, the amount of DNA content, the initiation time point of DNA replication, and the rate of DNA replication vary with the doubling time. An in-depth understanding of how DNA replication and cell division are regulated in bacteria not only is essential for understanding microbial physiology but also will enhance our ability to rationally design synthetic living systems.

In this project, we will combine synthetic biology with single-cell level analysis, such as microscopy and flow cytometry, and population-level analysis, including biochemistry, transcriptomics, and proteomics. Quantitative observations and analysis will elucidate the interconnections between bacterial cell growth, DNA replication, and cell division and reveal the underlying regulatory mechanisms at the molecular level.