Enhancing cobalamin (vitamin B12) production in E. coli to address demand and global security

提高大肠杆菌中的钴胺素（维生素 B12）产量以满足需求和全球安全

• 批准号: BB/S002197/1
• 负责人: Martin Warren
• 金额: $ 48.42万
• 依托单位: University of Kent
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FS002197%2F1
• 关键词: Enhancing; cobalamin; vitamin; B12; production

Anemia is a public health condition of epidemic proportions, affecting 30% of the worlds' population (2 billion people). The highest prevalence is in preschool-age children and pregnant women. The condition results in ill-health (weakness, cognitive-development), premature death and reduction in work capacity of entire populations, bringing serious economic consequences to countries and continents. Although anaemia has been recognized as a public health problem for many years, little progress has been reported and the global prevalence of anaemia remains unacceptably high. WHO and UNICEF emphasize the urgent need to combat anaemia and stress the importance of recognizing its multifactorial etiology for developing effective control programmes. Iron deficiency accounts for around a third of anaemia cases, but significantly vitamin B12 deficiency has been identified as one of the major components of pernicious (or non-iron deficient) anaemia, which is further associated with spina bifida, higher levels of brain atrophy in the elderly and is linked with the development of cardiovascular disease and diabetes. A world-wide B12-supplementation programme would have a significant effect but this has so far not been attempted because the current price of vitamin B12, which is also referred to as cobalamin, is prohibitively expensive, especially for developing countries where it is needed most. Moreover, around 90% of B12 is made in China which raises nutrition security issues in the event of conflict or natural disasters. Not only is the nutrient important for human health it is also important as a supplement for animal feeds and for certain industrial processes such as the biological production of methionine and 1,3-propanediol.Vitamin B12 is one of the few vitamins and nutrients that is produced through fermentation. It is also one of the lowest yielding processes with the nutrient being produced only at around 400 mg/L of culture. This low yield is coupled with a strain that grows very slowly making the overall production very inefficient. In this project we will apply a combination of rational and random screens to develop a high-yielding producer of B12 in E. coli, building on the pathway knowledge of the Warren group and the world-leading expertise of DuPont/Tate & Lyle in strain development and optimisation. The project will result in the generation of a strain that will produce B12 on the g/L scale, ensuring a ready supply of the nutrient for commercial and humanitarian requirements.This project will provide basic and fundamental insights into the control and regulation of the B12 pathway. Our work will help identify some of the key bottlenecks in the biosynthesis, which is one of the most complex found in biological systems, and develop methods to overcome these issues. The project aims to reduce of the complexity in the pathway by using biosynthetic enzymes that lack inhibitory constraints. The pathway will be engineered into E. coli using gene editing technology to allow for optimal expression of the relevant genes. The strain will be further engineered to allow for the cellular procurement of the various building blocks that are required in the construction of the molecule. This project therefore looks to apply synthetic biology approaches to a current real-world problem and in so-doing will deliver a strain that will have enormous benefit to both industry and the nutrition markets.For this LINK project, DuPont/Tate & Lyle will provide a total of £470k, including a £100k cash investment, which will go towards funding a full-time technician.

贫血是一种流行性的公共卫生状况，影响到世界人口的30%（20亿人）。患病率最高的是学龄前儿童和孕妇。这种情况导致健康不良（虚弱、认知发育）、过早死亡和整个人口工作能力下降，给各国和各大洲带来严重的经济后果。虽然多年来贫血症已被确认为一个公共卫生问题，但报告的进展甚微，全球贫血症流行率仍然高得令人无法接受。世卫组织和儿童基金会强调迫切需要防治贫血症，并强调必须认识到贫血症的多因素病因，以制定有效的控制方案。缺铁约占贫血病例的三分之一，但值得注意的是，维生素B12缺乏已被确定为恶性（或非缺铁）贫血的主要组成部分之一，这与脊柱裂、老年人脑萎缩程度较高有关，并与心血管疾病和糖尿病的发展有关。世界范围的B12补充方案将产生重大影响，但迄今尚未尝试，因为维生素B12（也称为钴胺素）目前的价格高得令人望而却步，特别是对最需要它的发展中国家而言。此外，约90%的B12是在中国生产的，这在发生冲突或自然灾害时会引起营养安全问题。维生素B12不仅对人体健康很重要，而且作为动物饲料和某些工业过程的补充剂也很重要，例如蛋氨酸和1，3-丙二醇的生物生产。维生素B12是少数几种通过发酵生产的维生素和营养素之一。它也是产量最低的过程之一，仅在培养物中产生约400 mg/L的营养物质。这种低产量与生长非常缓慢的菌株相结合，使得整体生产非常低效。在本项目中，我们将采用合理筛选和随机筛选相结合的方法，在E.大肠杆菌，建立在沃伦集团的途径知识和杜邦/泰特和莱尔在菌株开发和优化的世界领先的专业知识。该项目将产生一个菌株，将产生B12的克/升规模，确保商业和人道主义需求的营养随时供应。该项目将提供基本和根本的见解B12途径的控制和调节。我们的工作将有助于确定生物合成中的一些关键瓶颈，这是生物系统中发现的最复杂的瓶颈之一，并开发克服这些问题的方法。该项目旨在通过使用缺乏抑制性限制的生物合成酶来降低途径的复杂性。该途径将被工程化到E.大肠杆菌中使用基因编辑技术，以允许相关基因的最佳表达。菌株将被进一步工程化以允许细胞采购分子构建中所需的各种结构单元。因此，该项目旨在将合成生物学方法应用于当前的现实问题，并将提供一种对行业和营养市场都有巨大好处的菌株。对于该LINK项目，杜邦/泰特和莱尔将提供总计47万英镑的资金，其中包括10万英镑的现金投资，用于资助全职技术人员。

项目成果

Zinc Substitution of Cobalt in Vitamin B 12 : Zincobyric acid and Zincobalamin as Luminescent Structural B 12 -Mimics

维生素 B 12 中钴的锌替代：锌钴酸和锌钴胺作为发光结构 B 12 模拟物

• DOI: 10.1002/ange.201908428
• 发表时间: 2019
• 期刊: Angewandte Chemie
• 作者: Kieninger C

Exploring the onset of B 12 -based mutualisms using a recently evolved Chlamydomonas auxotroph and B 12 -producing bacteria

使用最近进化的营养缺陷型衣藻和生产 B 12 的细菌探索基于 B 12 的互利共生的开始

• DOI: 10.1101/2022.01.04.474942
• 发表时间: 2022
• 作者: Bunbury F

Encyclopedia of Biological Chemistry III

生物化学百科全书III

• DOI: 10.1016/b978-0-12-809633-8.21387-3
• 发表时间: 2021
• 作者: Rich P