Engineering Rhodopseudomonas palustris for enhanced biohydrogen production

改造沼泽红假单胞菌以提高生物氢产量

• 批准号: 2763729
• 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: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2763729
• 关键词: Engineering; Rhodopseudomonas; palustris; enhanced; biohydrogen

Fossil fuels (oil, coal, and natural gas) dominate global energy sources but emit CO2, contributing to climate change. Their extraction harms the environment and is finite. Transitioning to cleaner, sustainable energy is essential. Renewables like wind, solar, hydro, and geothermal, plus alternative fuels (e.g., hydrogen and biofuels), are gaining traction. Hydrogen is promising. It's carbon-neutral and versatile, aiding decarbonization. Current hydrogen production, though, relies on fossil fuels, emitting CO2. Clean, renewable options like biohydrogen, produced biologically from organic matter using microbes, offer lower carbon footprints, energy efficiency, and waste management solutions.Microbial electrochemical technologies, notably microbial electrochemical cells (MECs), are used for biohydrogen production. Challenges include enhancing yield and production rate. Addressing these hinges on understanding microbial communities involved in biohydrogen production.Rhodopseudomonas palustris or R. palustris is one of the most attractive and potential candidates commonly utilised in MECs for biohydrogen production. It can fix both carbon and nitrogen. Hydrogen production is the side product of nitrogen fixation. The knowledge gap lies in how the metabolic modules of nitrogen fixation and hydrogen production are controlled in this bacterium. In this context, my project focuses on understanding the interaction among the genes responsible for hydrogen production in R. palustris and engineer them for enhanced biohydrogen production. Work package 1 Task 1.1- Characterisation of different industrial wastewater streams Wastewater from such industries will be explored and characterised for organic content. This will help to identify the wastewater streams that are rich in organic content. Task 1.2- Assessment of different strains of R. palustris that have shown hydrogen productionPreviously studied strains of R. palustris will be inoculated in the different waste streams and the extent of hydrogen production will be documented, enabling us to identify the best hydrogen producing strain. Work package 2Task 2.1- Identification of differentially expressed/regulated pathways The best hydrogen producing strain will be grown under nitrogen limiting or non-limiting conditions and will be subjected to comparative proteomic and transcriptomic analysis.Task 2.2- Validation of genes/regulatory proteins involved in hydrogen production Newly identified pathway components will be subjected to gene inactivation and later functional complementation to elucidate their role in H2 production. Work package 3 Task 3.1- Biological engineering Once the regulation of differentially expressed genes in the best characterised strain of R. palustris responsible for H2 production has been identified, the potential candidate genes will be subjected to further genetic modification (plasmid- based overexpression, genome integration, deregulation, deletion) with the aim of enhancing H2 production. Work package 4- Assessing hydrogen production in engineered R. palustris' strain in MEC. Task 4.1- MEC construction For this task, a two-chambered MEC system separated by a PEM (Nafion (Du Pont) will be used. Task 4.2- Evaluation of genetically engineered R. palustris' strain in MEC for improved hydrogen production The genetically modified strain vs its wildtype will be analysed for hydrogen production in the MEC constructed above. Work package 5 Task 5.1- With the aim to achieve improved hydrogen production, the MEC reactor will be optimised on the following factors:pH, Temperature, Electrode material. Work package 6 Task 6.1 Performing LCA To assess the environmental impact of MEC-based microbial hydrogen production compared to traditional methods, an LCA, from raw material utilisation to disposal, can be executed

化石燃料（石油、煤炭和天然气）在全球能源中占主导地位，但它们排放的二氧化碳加剧了气候变化。它们的开采对环境有害，而且是有限的。向更清洁、可持续的能源过渡至关重要。风能、太阳能、水能和地热等可再生能源，加上替代燃料（如氢和生物燃料），正获得越来越多的关注。氢很有前途。它是碳中性的，用途广泛，有助于脱碳。然而，目前的氢气生产依赖于化石燃料，排放二氧化碳。清洁、可再生的选择，如生物氢，利用微生物从有机物质中产生，提供更低的碳足迹、能源效率和废物管理解决方案。微生物电化学技术，特别是微生物电化学电池（MECs），被用于生物制氢。挑战包括提高产量和生产率。解决这些问题取决于了解参与生物制氢的微生物群落。古红假单胞菌（Rhodopseudomonas palustris或R. palustris）是mec中最具吸引力和潜在的生物制氢候选菌之一。它可以固定碳和氮。产氢是固氮的副产品。知识差距在于这种细菌如何控制固氮和产氢的代谢模块。在此背景下，我的项目侧重于了解在palustris中负责制氢的基因之间的相互作用，并设计它们来增强生物制氢。工作包1任务1.1-不同工业废水流的特征将对来自这些工业的废水进行探索和表征，以确定其有机含量。这将有助于确定有机含量丰富的废水流。任务1.2-评估已经显示出产氢的不同palustris菌株先前研究的palustris菌株将在不同的废物流中接种，并记录产氢的程度，使我们能够确定最佳的产氢菌株。最佳产氢菌株将在限氮或非限氮条件下生长，并将进行比较蛋白质组学和转录组学分析。新发现的途径成分将进行基因失活和后来的功能互补，以阐明它们在氢气产生中的作用。一旦在最具特征的palustris菌株中确定了负责H2生产的差异表达基因的调控，潜在的候选基因将受到进一步的基因修饰（基于质粒的过表达，基因组整合，去监管化，删除），目的是提高H2生产。工作包4-评估MEC中工程palustris菌株的产氢量。任务4.1- MEC结构对于本任务，将使用由PEM （Nafion (dupont)）分隔的双室MEC系统。任务4.2-评价转基因palustris菌株在MEC中的产氢效果。将对转基因菌株与其野生型在上述MEC中的产氢效果进行分析。工作包5任务5.1-为了提高氢气产量，MEC反应器将根据以下因素进行优化：pH值、温度、电极材料。与传统方法相比，为了评估基于mec的微生物制氢对环境的影响，可以执行从原材料利用到处置的LCA