Biosynthesis, Regulation and Engineering of Bacterial Carbon Fixation Machinery

细菌固碳机制的生物合成、调控与工程

• 批准号: BB/M024202/1
• 负责人: Luning Liu
• 金额: $ 60.21万
• 依托单位: University of Liverpool
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2015
• 资助国家: 英国
• 起止时间: 2015 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FM024202%2F1
• 关键词: Biosynthesis; Regulation; Engineering; Bacterial; Carbon

The single-cell cyanobacteria are among the most abundant organisms on earth. They created and help to sustain our atmosphere, and account for an estimated 20-30 % of current global carbon fixation. To enhance carbon fixation, cyanobacteria develop small compartments, called carboxysomes, to absorb carbon dioxide and transform it to chemical energy by the process named photosynthesis. These highly efficient machines are structurally defined by an outer protein-based shell and internal highly concentrated CO2-fixing enzymes. The shell is composed of many distinct proteins, and serves as a selective "barrier" for the passage of specific molecules into and out of the compartments. At present, there are great concerns over global food and energy security. How can we improve the food supply to keep pace with the world population? How can we develop environmentally sustainable solutions for food and energy production? Producing and engineering of synthetic carboxysomes and introducing them into other organisms, particularly plants, has significant potential for improving photosynthesis, carbon sequestration and crop yield. As the cyanobacteria is evolutionarily close to the plant chloroplast, lessons learned from the cyanobacteria will be very informative to plant sciences and engineering. Recent developments in synthetic biology have opened the door to generating artificial biological machines by providing the necessary strategies and approaches. However, producing functional carboxysomes in other organisms requires comprehensive knowledge about their development and physiological regulation in their natural hosts, the cyanobacteria. The aims of this project are to elucidate comprehensively how cyanobacterial cells create these specialised compartments, how their activities are dynamically regulated within the cells in response to the changing environment, and how these machines function together with other cellular activities in the entire metabolic network within cells. In the first part of this research project, we will use a special optical microscopy to watch the development and distribution of carboxysomes in living cells, and study how these organelles are regulated within the cells grown under different environmental conditions. The second section will characterise how these organelles interact and function together with other cellular components to achieve their metabolic performance. Next we will find out how multiple proteins are organised in order to build the organelle shape. We will develop a computer programme to build a model of the compartment and simulate the protein dynamics and passage of molecules in and out of the compartment. Advanced understanding of the compartment structure, function and regulation derived from the three sections is important for genetic engineering of novel biological machines with appropriate functionality. In the last section, we will use the knowledge learned from the cyanobacterial cells to synthesise artificial biological machines with carbon fixation activities.This work represents a model for studying the development of complex biological machines within cells. It will teach us about how thousands of proteins can assemble together by themselves to form a functional entity within cells, and what regulatory strategies are developed by the cells to lead the development and function of these machines. In translational terms, this work will provide an instructive example for the design and engineering of novel biological "factories" for specific cellular activities and physiology. If we can conduct genetic engineering to enable higher plants to develop synthetic cyanobacterial carbon-fixing machines, it will significantly enhance food and energy production.

单细胞蓝藻是地球上最丰富的生物之一。它们创造并帮助维持我们的大气，估计占目前全球碳固定的20- 30%。为了增强固碳能力，蓝藻发育出一种叫做羧酸体的小隔间来吸收二氧化碳，并通过光合作用将其转化为化学能。这些高效的机器在结构上由外部的蛋白质外壳和内部高浓度的二氧化碳固定酶来定义。外壳由许多不同的蛋白质组成，并作为一个选择性的“屏障”，使特定分子进出隔室。当前，全球粮食和能源安全问题令人十分担忧。我们怎样才能改善粮食供应以跟上世界人口的增长呢？我们如何为粮食和能源生产制定环境可持续的解决方案？生产和工程合成羧酶体并将其引入其他生物，特别是植物，对改善光合作用、碳固存和作物产量具有重大潜力。由于蓝藻在进化上与植物叶绿体接近，从蓝藻中吸取的经验教训将对植物科学和工程有很大的帮助。合成生物学的最新发展通过提供必要的策略和方法，为制造人工生物机器打开了大门。然而，在其他生物体中生产功能性羧基体需要对其自然宿主蓝藻的发育和生理调节有全面的了解。该项目的目的是全面阐明蓝藻细胞如何创建这些专门的隔间，它们的活动如何在细胞内动态调节以响应不断变化的环境，以及这些机器如何在细胞内的整个代谢网络中与其他细胞活动一起发挥作用。在本研究项目的第一部分，我们将使用一种特殊的光学显微镜来观察活细胞中羧基体的发育和分布，并研究这些细胞器在不同环境条件下生长的细胞中是如何被调节的。第二部分将描述这些细胞器如何与其他细胞成分相互作用并一起发挥作用以实现其代谢性能。接下来，我们将了解多种蛋白质是如何组织起来形成细胞器形状的。我们将开发一个计算机程序来建立一个隔室模型，模拟蛋白质动力学和分子进出隔室的通道。从这三个部分衍生出的对隔室结构、功能和调控的深入了解，对于具有适当功能的新型生物机器的基因工程具有重要意义。在最后一节中，我们将利用从蓝藻细胞中学到的知识来合成具有固碳活性的人工生物机器。这项工作为研究细胞内复杂生物机器的发展提供了一个模型。它将告诉我们成千上万的蛋白质如何自己组装在一起，形成细胞内的功能实体，以及细胞制定了哪些调节策略来引导这些机器的发展和功能。在翻译方面，这项工作将为特定细胞活动和生理的新型生物“工厂”的设计和工程提供一个指导性的例子。如果我们能够进行基因工程，使高等植物能够开发合成的蓝藻固碳机器，这将大大提高粮食和能源的产量。

项目成果

Incorporation of Functional Rubisco Activases into Engineered Carboxysomes to Enhance Carbon Fixation.

• DOI: 10.1021/acssynbio.1c00311
• 发表时间: 2022-01-21
• 期刊: ACS synthetic biology
• 影响因子: 4.7
• 作者: Chen T;Fang Y;Jiang Q;Dykes GF;Lin Y;Price GD;Long BM;Liu LN
• 通讯作者: Liu LN

Insights into the Origin of Distinct Medin Fibril Morphologies Induced by Incubation Conditions and Seeding.

• DOI: 10.3390/ijms19051357
• 发表时间: 2018-05-03
• 期刊: International journal of molecular sciences
• 影响因子: 5.6
• 作者: Davies HA;Lee CF;Miller L;Liu LN;Madine J
• 通讯作者: Madine J

Producing fast and active Rubisco in tobacco to enhance photosynthesis.

• DOI: 10.1093/plcell/koac348
• 发表时间: 2023-02-20
• 期刊: PLANT CELL
• 影响因子: 11.6
• 作者: Chen, Taiyu;Riaz, Saba;Davey, Philip;Zhao, Ziyu;Sun, Yaqi;Dykes, Gregory F.;Zhou, Fei;Hartwell, James;Lawson, Tracy;Nixon, Peter J.;Lin, Yongjun;Liu, Lu-Ning
• 通讯作者: Liu, Lu-Ning

Dissecting the Native Architecture and Dynamics of Cyanobacterial Photosynthetic Machinery.

• DOI: 10.1016/j.molp.2017.09.019
• 发表时间: 2017-11-06
• 期刊: Molecular plant
• 影响因子: 27.5
• 作者: Casella S;Huang F;Mason D;Zhao GY;Johnson GN;Mullineaux CW;Liu LN
• 通讯作者: Liu LN

Molecular simulations unravel the molecular principles that mediate selective permeability of carboxysome shell protein

分子模拟揭示了介导羧基体壳蛋白选择性渗透的分子原理

• DOI: 10.1101/2020.06.14.151241
• 发表时间: 2020
• 作者: Faulkner M