Team:Tartu TUIT/Project
Project Description
Yeasthylene
Nowadays society is deeply dependent on non-renewable energy sources, such as oil and gas. These sources are mainly used as fuels, intended to meet the energy and electricity demands of today’s world. However, a wide range of other important chemical compounds are produced from petroleum, most notably hydrocarbon monomers such as ethylene (C2H4). The demand on ethylene has only been increasing during the last decade; the average annual growth from 2007 to 2014 was 2.2%, whereas it is predicted that the growth would increase to 3.6% for the years 2014-2020. This high demand is mainly due to the fact that ethylene is rather multipurposed, and it is used as an essential building block in many chemical compounds. Its most commonly used polymer product, polyethylene, is a main compound in many plastic materials.The main aim of our project is to find an alternative and biological way of producing ethylene. In this project, two yeast subpopulations with completely different roles will be genetically modified to produce ethylene from sucrose. The focus of the project is set to make those subpopulations dependent on each-other and to provide a balanced growth. The subpopulation approach represents a more efficient method than cloning the whole pathway into one population, especially when longer heterologous pathways will be used in the future to produce more complex chemicals. Energy gain due to lower metabolic burden and balanced co-factor metabolism will result in higher production rates. We will make both of our subpopulations unable to metabolise sucrose. However, in the second subpopulation the suc2 gene, responsible for conversion of sucrose to glucose and fructose, will be overexpressed. The protein will be automatically secreted into the sucrose media where it will convert sucrose into glucose and fructose. Our second subpopulation will not be able to metabolise glucose or fructose. In this way, all the glucose or fructose will be used up by the first subpopulation. The first subpopulation will naturally convert glucose and fructose into ethanol. Since the second subpopulation is not able to metabolise sucrose, glucose or fructose it will use ethanol as it only carbon source. This ethanol will enter the TCA cycle and will eventually be converted into ethylene through EFE enzyme which will be introduced to the second subpopulation.
