Toward libraries for increased bio plastic production in cyanobacteria
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesisAlternative title
Metagenomiska bibliotek att förbättra cyanobakterier bioplast produktion (Swedish)
Cyanobateria are promising cell factories due to their minimal nutrient requirements and utilization of asmospheric carbon di-oxide as its sole carbon source. In particular, polyhydroxybutyrate (PHB) is an industrially useful bio plastic that is produced naturally by some cyanobacteria. Furthermore, PHB biosynthetic pathway is a starting point for production of the biofuel, 1-butanol. There has been much genetic engineering effort toward increasing the production of PHB from cyanobacteria. These have been focused on increasing the pool of acetyl-CoA precursor, or increasing the amount of the reductant NADPH. The upstream process for increasing these reactants is complex and involves many genes. In this contect, cyanobacteria libraries will contribute to reveal genes or gene fragments that are responsible for production of PHB, alkanes and other high value compounds. In pursuit of finding these novel genes or genefragments, a transcription factor library is created in this study with 50 transcription factors. Furthermore, the process is optimized towards the creation of genomic fragment library and metagenomic fragment library with 26 diverse strains. Membersof the transcription factor library are over-expressed by a PHB - producing host Synechocystis PCC 6803 and the process towards creation of genomic and metagenomic libraries is optimized. The members of the metagenomic library can be screened for increased PHB, alkanes, lactate and other high value products and the potential members can be isolated and characterized.
Place, publisher, year, edition, pages
cyanobacteria, metagenomics, libraries, bioplastic, transcription factors
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-173649OAI: oai:DiVA.org:kth-173649DiVA: diva2:854226