Sustainable bioproducts from low cost methane gas

来自低成本甲烷气体的可持续生物产品

• 批准号: 2182233
• 金额: --
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Studentship
• 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=studentship-2182233
• 关键词: Sustainable; bioproducts; low; cost; methane

BACKGROUND: To compete with existing biopruducts manufacturing processes based on petrochemical derived raw materials, low cost feedstocks for biological fermentation processes are essential, since the feedstock typically equates to >60% of the overall production cost. In addition, the yield based on carbon needs to be high, which is very difficult to achieve with sugars or cellulosic feedstocks with a high oxygen content, since the oxygen is lost as CO2. Methane (CH4) is an abundant and cheap carbon resource, but is currently under-utilised as a feedstock for industrial biotechnology. Surplus methane is often released during oil extraction and simply flared (burnt without capturing the energy or carbon content). Many natural gas reserves are 'stranded' and uneconomic to recover. Methane is also a major component of biogas produced on a large scale by anaerobic digestion, technology that is well established in the EU. Currently, most biogenic methane is burnt for energy and has relatively little value. Today, methane is a low cost fermentation feedstock and also sustainable given the many sources available and current wastage. Therefore, methane provides an exciting feedstock opportunity for fermentation and conversion into high value biochemical metabolites (lipids, proteins and feeds). As the world leading methane-based protein producer, Calysta has filed patents for the use of methanotrophs in the commercial-scale production of nutritional ingredients, chemicals, biofuels and feed from methane. A disruptive production process based on CH4 would accelerate the growth and market penetration of biobased products considerably. Aerobic methanotrophs represent the only available route for methane bioconversion, activating methane to methanol via methane monooxygenase (MMO) and subsequently converting methanol to formaldehyde en route to by-products. There are currently more than 15 recognised genera of methanotrophs, with many recent publications showing the isolation of new species or strains and genome sequences, within which Methylococcus capsulatus is the model organism and the most common chassis in attempts to produce biomass for use as single-cell protein in animal feed. As part of BBSRC NIBB C1Net POC (Metabolic modelling to support synthetic biology in C1Net organisms) project, a genome scale model (GSM) of M. capsulatus (Bath) was generated on the basis of the annotation obtained from BioCyc. This model was shown to represent a cell system capable of generating all amino acids, nucleotides, generic lipid and carbohydrate using methane as the sole carbon source. It was also shown that the cell is capable of generating the industrially useful bioproducts such as succinate. This GSM will be used in the project. AIM: In this project, we will explore the bottlenecks of using methane as a feedstock in continuous fermentations in both lab (1L, 10L) and demo (5000L) scales; to improve the rates and energy efficiencies of methane uptake, as well as approaches to engineer high-productivity methane conversion organisms. STRATEGY: Our aim will be progress through the following activities:- (i) identifying M.capsulatus growth bottlenecks in fermenters through meticulous designed RNA seq experiments; (ii) implementing the requisite random mutagenesis transposon technologies in M. capsulatus; (iii) using semi-robotic high throughput technology screening for desired phenotype and thereafter the gene/genes affecting; (v) follow GSM's instruction, rational knock out genes and pathways to increase CH4 assimilation. OUTCOME:Working with one of the world's leading C1 companies, the student will develop and demonstrate the potential of M. capsulatus as whole cell protein feed from low cost methane gas. This will allow avoidance of competition with food and land resources while at the same time providing benefits to the environment and society through a reduction in GHG emissions.

背景：与现有的基于石化衍生的原材料的现有生物层面制造工艺竞争，生物发酵过程的低成本原料是必不可少的，因为原料通常等于总体生产成本的60％。此外，基于碳的产量必须高，因为氧气作为CO2丢失，因此糖或纤维素原料很难实现。甲烷（CH4）是一种丰富且廉价的碳资源，但目前被视为工业生物技术的原料。甲烷多余的甲烷通常在油提取过程中释放，并简单地爆发（燃烧而不捕获能量或碳含量）。许多天然气储量被“滞留”，不经济恢复。甲烷也是通过厌氧消化大规模生产的沼气的主要组成部分，在欧盟中已建立了良好的技术。目前，大多数生物甲烷都被燃烧而成，价值相对较小。如今，甲烷是一种低成本的发酵原料，鉴于许多可用来源和当前浪费，也是可持续的。因此，甲烷为发酵和转化为高价值生物化学代谢产物（脂质，蛋白质和饲料）提供了令人兴奋的原料机会。作为世界领先的基于甲烷的蛋白质生产剂，Calysta已申请了专利，用于在营养成分，化学物质，生物燃料和甲烷饲料的商业规模生产中使用甲烷营养。基于CH4的破坏性生产过程将大大加速生物基产品的增长和市场渗透。有氧甲烷营养物是甲烷生物转化的唯一可用途径，通过甲烷单加氧酶（MMO）将甲烷激活至甲醇，然后将甲醇转化为甲醇，以甲醇甲醇，从而在副产品途中将甲烷转化为甲醇。目前，有15种以上公认的甲嗜性属属，许多最近的出版物表明了新物种或菌株和基因组序列的隔离，其中甲基甲虫是模型的生物体，也是最常见的机构，试图用作单个生物量以单个形式的生物量动物饲料中的细胞蛋白。作为BBSRC NIBB C1NET POC（支持C1NET生物中合成生物学的代谢建模）项目的一部分，M. capsulatus（BATH）的基因组量表模型（GSM）是根据生物循环获得的注释产生的。该模型被证明代表了一种能够生成所有氨基酸，核苷酸，通用脂质和碳水化合物的细胞系统，将甲烷作为唯一的碳源。还表明该细胞能够产生工业上有用的生物产品，例如琥珀酸酯。该GSM将在项目中使用。目的：在这个项目中，我们将探索在实验室（1L，10L）和演示（5000L）尺度的连续发酵中使用甲烷作为原料的瓶颈；为了提高甲烷摄取的速率和能量效率，以及工程甲烷转化生物的高生产率的方法。 策略：我们的目标是通过以下活动进行： - （i）通过精心设计的RNA SEQ实验确定发酵罐中的大型生长瓶颈； （ii）在M. capsulatus中实施必要的随机诱变转座技术； （iii）使用半无菌高通量技术筛选进行所需的表型，然后使用影响基因/基因； （v）遵循GSM的指示，理性敲除基因和增加CH4同化的途径。结果：与全球领先的C1公司之一合作，该学生将开发并证明Capsulatus M. capsulatus作为全细胞蛋白从低成本甲烷气体中饲料的潜力。这将避免与食品和土地资源竞争，同时通过减少温室气体排放为环境和社会提供利益。