The role of acylation in cellulose synthesis

酰化在纤维素合成中的作用

• 批准号: BB/P01013X/1
• 负责人: Simon Turner
• 金额: $ 58.2万
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FP01013X%2F1
• 关键词: role; acylation; cellulose; synthesis

Cellulose is the major component of many plant cells walls and is considered to be the world's most abundant naturally occurring polymer. Cellulose is actually composed on many chains of the sugar (glucose) units bonded together to form something known as the microfibril. These microfibrils have unique physical properties that are exploited by plants. Cellulose microfibrils are ubiquitous among higher plants where they are important in determining how plant cells grow and also determining how strong the plant material is. We already exploit the properties of cellulose to make paper and cotton, however, cellulose has the potential to be used in a wide range of other applications including novel materials and as a renewable source of sugars for the production of biofuels and chemicals. One of the major advantages of using plant based material is that plants obtain their carbon from the atmosphere in form of CO2 and so using plant material such as cellulose is not only renewable, but dramatically reduces net carbon emission into the atmosphere compared to the use of fossil fuels. Cellulose is synthesis by a unique enzyme complex that sits in the plasma membrane that surrounds the contents of every cell. Each cellulose synthase complex makes around 18 chains that bond together to form a microfibril. These microfibrils are rigid structures and so as the complex adds sugars to the growing chains, it is effectively driven along the plasma membrane. Given the large size of the complex, it will cause severe local disruption of the plasma membrane. The plasma membrane is composed of lipids that provide a fluid environment that allows movement of the cellulose synthase complex, but it is essential the cells maintain the integrity of the plasma membrane for its viability. Movement of the cellulose synthase complex is governed by long tubular structures known as microtubules that sit close to the plasma membrane and guide the movement of cellulose synthase complex and hence orientation of the cellulose microfibrils. Orientation of cellulose microfibrils is essential for the growth of plant cells and has a major influence on their physical properties.Although cellulose is very abundant, there are several technological challenges associated with studying cellulose, including separating it from other parts of the cell wall and breaking up its strongly bonded structure. Surprisingly, the vast importance of cellulose is not matched by our understanding of the processes behind its formation. We have become interested in how the individual components of the cellulose synthase complex are modified by the addition of fatty acid groups. These fatty acid groups are very hydrophobic and have a very high affinity for membranes. We believe this has an essential role in locking the cellulose synthase complex into the plasma membrane and preventing it "popping out" as the complex moves through the membrane. The cells are also faced with another logistical problem, as the plasma membrane is crowded with many other components. We now want to look at how the plasma membrane might be partitioned to allow unimpeded movement of the cellulose synthase complex. We will investigate how the addition of hydrophobic fatty acid groups both to the cellulose synthase complex and to the underlying microtubules contributes their co-localisation and the ability of the cell to form membrane partitions at sites of cellulose synthesis.Ultimately this work should provide a framework that we can use to make changes that may alter the properties of the cellulose that it produces. It is already known that some mutations reduce the crystalinity of the cellulose and so make it easier to breakdown into its constituent sugars that maybe used for biofuels or other industrial applications. It is likely that a better understanding of the local environment in which plants make cellulose may help us to alter other cellulose properties such as microfibril length.

纤维素是许多植物细胞壁的主要组成部分，被认为是世界上最丰富的天然聚合物。纤维素实际上是在糖（葡萄糖）单位的许多链中组成的，形成了一种称为微纤维的东西。这些微纤维具有植物利用的独特物理特性。纤维素微纤维在较高植物中无处不在，在这些植物中，它们在确定植物细胞的生长以及确定植物材料的坚固程度上很重要。我们已经利用了纤维素的特性来制作纸张和棉花，但是，纤维素有可能在其他广泛的应用中使用，包括新型材料和可再生糖来源，用于生产生物燃料和化学物质。使用基于植物的材料的主要优点之一是，植物以二氧化碳的形式从大气中获取碳，因此与使用化石燃料相比，使用诸如纤维素之类的植物材料（例如纤维素）可以大大减少净碳排放到大气中。纤维素是由围绕每个细胞含量的质膜中的独特酶复合物合成的。每个纤维素合酶复合物的生产约18个链，将粘合在一起形成微纤维。这些微纤维是刚性结构，因此随着络合物在生长的链中增加糖，它被有效地沿着质膜驱动。鉴于该复合物的大尺寸，它将导致质膜严重局部破坏。质膜由提供允许纤维素合酶复合物运动的流体环境的脂质组成，但必不可少的细胞维持质膜的完整性以使其生存能力。纤维素合酶复合物的运动由长管结构（称为微管）的长管结构，它们位于质膜附近，并指导纤维素合酶复合物的运动，因此纤维素微纤维的方向。纤维素微纤维的方向对于植物细胞的生长至关重要，并且对其物理特性产生了重大影响。尽管纤维素非常丰富，但与研究纤维素相关的技术挑战存在一些技术挑战，包括将其与细胞壁的其他部分分开并打破其强键结构。令人惊讶的是，纤维素的巨大重要性与我们对其形成过程背后的过程的理解相匹配。我们已经对如何通过添加脂肪酸基团改变了纤维素合酶复合物的各个成分感兴趣。这些脂肪酸基非常疏水，对膜具有很高的亲和力。我们认为，这在将纤维素合酶复合物锁定到质膜中具有至关重要的作用，并防止随着膜通过膜的移动而“弹出”。细胞也面临着另一个后勤问题，因为质膜挤满了许多其他成分。现在，我们想研究如何对质膜进行分割，以允许纤维素合酶复合物的不受阻碍运动。我们将研究如何在纤维素合酶复合物中添加疏水性脂肪酸基团以及潜在的微管如何促进它们的共定位，以及细胞在纤维素合成位点形成膜分隔的能力。我们应该提供一个框架，我们可以使用该框架来改变该构图的属性。众所周知，某些突变会减少纤维素的结晶度，因此使其更容易分解成其可能用于生物燃料或其他工业应用的组成糖。对植物使纤维素产生的局部环境的理解很可能有助于我们改变其他纤维素特性，例如微纤维长度。

项目成果

An atlas of Arabidopsis protein S-Acylation reveals its widespread role in plant cell organisation of and function

• DOI: 10.1101/2020.05.12.090415
• 发表时间: 2020-05
• 期刊: bioRxiv
• 作者: M. Kumar;P. Carr;S. Turner

Exploiting CELLULOSE SYNTHASE (CESA) Class Specificity to Probe Cellulose Microfibril Biosynthesis

• DOI: 10.1104/pp.18.00263
• 发表时间: 2018-05-01
• 期刊: PLANT PHYSIOLOGY
• 影响因子: 7.4
• 作者: Kumar, Manoj;Mishra, Laxmi;Turner, Simon
• 通讯作者: Turner, Simon

The role of lipid-modified proteins in cell wall synthesis and signaling.

• DOI: 10.1093/plphys/kiad491
• 发表时间: 2023-12-30
• 期刊: PLANT PHYSIOLOGY
• 影响因子: 7.4
• 作者: Quinn, Oliver;Kumar, Manoj;Turner, Simon
• 通讯作者: Turner, Simon

Flexible and digestible wood caused by viral-induced alteration of cell wall composition.

• DOI: 10.1016/j.cub.2022.06.005
• 发表时间: 2022-08-08
• 期刊: CURRENT BIOLOGY
• 影响因子: 9.2
• 作者: Allen, Holly;Zeef, Leo;Morreel, Kris;Goeminne, Geert;Kumar, Manoj;Gomez, Leonardo D.;Dean, Andrew P.;Eckmann, Axel;Casiraghi, Cinzia;McQueen-Mason, Simon J.;Boerjan, Wout;Turner, Simon R.
• 通讯作者: Turner, Simon R.