NPIF: A synthetic biology approach to engineering novel commercial variants of cyanobacterial pigment proteins

蓝藻是生产商业上重要的色素蛋白的生物平台，如藻红蛋白和c -藻蓝蛋白（C-PC），广泛用于食品、营养、分析和制药行业(1)。苏格兰生物能源公司（http://www.scotbio.com/）将C-PC视为开发的杰出候选者，目标是在工业规模上生产高质量的C-PC。苏格兰生物能源公司已经投资了大量的研发，以改善上游和下游的加工，并生产新的蓝藻菌株，增加C-PC产量。在结构上，C-PC由两个载脂蛋白和藻蓝胆素发色团共价结合的复合体组成，它们共同构成了光收集藻胆体复合体中最丰富的色素蛋白(2)。然而，C-PC既热敏又光敏，这对存储和使用造成了相当大的限制。该项目建议使用合成生物学方法对商业上相关的蓝藻菌株进行工程设计，以生产具有增强的耐热性、耐光性和改进的荧光团特性的C-PC的新变种(3)。合成C-PC变体将降低下游成本，预计具有重要的市场价值。这个项目是一个很好的培训机会，可以接触到各种各样的分子和生理方法，并参与商业翻译活动。您将开发基于蓝藻分子技能的专业知识，包括DNA， RNA和蛋白质分析（例如qRT-PCR， Western blot，离子交换色谱），以及光合生理学和荧光技术。该项目将采用定向进化方法来进化参与C-PC生物合成的蛋白质，以改善C-PC的特性。有希望的蛋白质变体将被整合到商业相关菌株中，以测试它们的性能和生理影响。因此，您将设计，测试和模拟新的蓝藻菌株表达工业上有利的C-PC形式的性能。你将有大量的机会在定期会议上展示你的研究，包括国内和国际会议。与苏格兰生物能源整合并与英国工业战略保持一致概述的项目与苏格兰生物能源的商业目标直接相关。新的色素生产菌株将首先在实验室条件下进行测试，然后在苏格兰生物能源公司进行预商业规模的测试。候选人将通过定期计划的月度会议保持密切联系，讨论进展。候选人将在项目的第4年（第一或第二季度）在苏格兰生物能源公司进行为期3个月的专门安置，以测试在商业前数量下最有希望的菌株的性能。生长和产品产量将在实验室生物反应器优化的光和温度条件下进行比较。该项目与英国工业战略的几个支柱直接相关：研究将直接有助于高价值产品的商业化，技能发展，支持企业成长，培养世界领先的行业（苏格兰有一个不断增长的微藻工业规模生产IB部门和强大的联合学术部门）。

Cyanobacteria are an established bioplatform for the production of commercially important pigment proteins, such as phycoerythrin and C-phycocyanin (C-PC), which are used widely in the food, nutritional, analytical and pharmaceutical industries(1). Scottish Bioenergy (http://www.scotbio.com/) view C-PC as an outstanding candidate for exploitation and aims to produce high-quality C-PC at industrial scale. Scottish Bioenergy has already invested in significant R&D to improve upstream and downstream processing and to produce new cyanobacterial strains with increased C-PC yields. Structurally, C-PC consists of a covalently bonded complex of two apoproteins and phycocyanobilin chromophores, which together form the most abundant pigment protein of the light-harvesting phycobilisome complex(2). However, C-PC is both heat- and light-sensitive, which places considerable constraints on storage and usage. This project proposes to use a synthetic biology approach to engineer commercially relevant cyanobacterial strains to produce new variants of C-PC with increased thermotolerance, light resistance and improved fluorophore properties(3). Synthetic C-PC variants will reduce downstream costs and are predicted to have significant market value.TrainingThis project is an outstanding training opportunity to engage with a wide variety of molecular and physiological approaches, and to be involved in commercial translation activities. You will develop expertise in cyanobacterial-based molecular skills, including DNA, RNA and protein analyses (e.g. qRT-PCR, Western blot, ion exchange chromatography), and photosynthetic physiology and fluorescence techniques. The project will employ directed evolution approaches to evolve proteins involved in C-PC biosynthesis for C-PCs with improved characteristics. Promising protein variants will be integrated into commercially relevant strains to test their performance and physiological impact. Thus, you will engineer, test and model the performance of new cyanobacteria strains expressing industrially favourable C-PC forms. There will be abundant opportunity for you to present your research at regular meetings, including national and international conferences.Integration with Scottish Bioenergy and Alignment to the UK Industrial StrategyThe outlined project links directly with the commercial goals of Scottish Bioenergy. Novel pigment producing strains will be tested first under lab conditions, and then at pre-commercial scale with Scottish Bioenergy. The candidate will maintain close ties through regular planned monthly meetings, to discuss progress. The candidate will perform a dedicated 3-month placement at Scottish Bioenergy in year 4 (first or second quarter) of the project to test the performance of the most promising strains under pre-commercial quantities. Growth and product yields will be compared under light and temperature conditions optimised in lab-based bioreactors. The project is directly relevant to several of the pillars of the UK industrial strategy: research that will directly contribute to commercialisation of a high value product, skills development, supporting businesses to grow, and cultivating world-leading sectors (Scotland has a growing IB sector for industrial scale production of microalgae and a strong allied academic sector).