Study of polyhydroxybutyrate production in Escherichia coli
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesisAlternative title
Studier av produktion av polygydroxbutyrat i Escherichia coli (Swedish)
With the purpose of commercializing polyhydroxyalkanoates (PHA), a biosynthetic and biodegradable plastic, a considerable effort has been dedictated to reducing the production cost, through the development of bacertial strains and more efficient fermentation/recovery processes from cheap carbon sources. Since the discovery of phb genes, many genes encoding enzymes from the PHA pathway have been cloned from different organisms. The broad variety of PHA-producing microbes would prepresent a vast spectrum of intracellular conditions to which these enzymes would have to be adapted. The present work is within this purpose and had as goal to study the polyhydroxyalkanoates (PHB) production, from Escherichia coli AF1000 strain transformed with plasmid pCJY02 harboring, phbA, phbB genes from Ralstonia eutropha and phaC gene from Pseudomonas stutzeri 1317, cultivated in minimal medium supplemented with glucose.
The maximum amount of PHB obtained was 0,917 gr.L-1, PHB content of 4,6% and cell mass of 19,8 gr.L-1, through fed-batch cultivation. In order to improve these results, further work on the strain metabolism and plasmid construct is necessary, therefore a set of different approaches to achieve the required improvements are discussed throughout this work.
Place, publisher, year, edition, pages
PHB, nutrient limitation, batch, fedbatch cultivation, Escherichia coli
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-150482OAI: oai:DiVA.org:kth-150482DiVA: diva2:744716