2026-05-22T18:14:42Zhttps://keep.lib.asu.edu/oai/request

oai:keep.lib.asu.edu:node-1686692024-12-23T18:01:48Zoai_pmh:alloai_pmh:repo_items

168669 https://hdl.handle.net/2286/R.2.N.168669 http://rightsstatements.org/vocab/InC/1.0/ All Rights Reserved 2022 2024-05-01T15:58:27 43 pages Masters Thesis Academic theses Text eng Brookhouser, Brendan Nielsen, David R Tonkovich, Anna L Varman, Arul M Arizona State University Partial requirement for: M.S., Arizona State University, 2022 Field of study: Chemical Engineering Alkanolamines are useful as building blocks for a variety of applications, ranging from medical applications such as drug and gene delivery. In this work, Escherichia coli was investigated as a viable candidate for the production of 5-amino-1-pentanol (5-AP). Taking advantage of the existing L-lysine degradation pathway, a novel route to 5-AP was constructed by co-expressing the genes cadA (encoding lysine decarboxylase, responsible for the conversion of L-lysine to cadaverine) and patA (encoding putrescine aminotransferase, responsible for the conversion of cadaverine to 5-amino-1-pentanal), followed by the endogenous reduction of 5-amino-pentanal (5-APL) to 5-AP. To avoid the competing conversion of 5-APL to 5-amino-1-pentanoate and avoid accumulation of byproduct 1-Δ-piperideine, further host engineering was performed to delete the gene patD also known as prr (encoding 5-amino-pentanal dehydrogenase). Flask scale fermentation experiments in minimal medium of the newly constructed pathway was conducted where 62.6 mg/L 5-AP was observed to be produced. It was hypothesized that 5-AP production could be boosted by optimizing production medium to M10 media. However, change in the culture medium resulted in the production of just 51 mg/L 5-AP. Shifts observed in HPLC chromatogram peaks made it difficult to conclude exact titers of 5-AP and can be further improved by exploring different analysis methods and optimization of the method currently in place. Microbiology Biochemistry Cellular Biology 5-Amino-1-Pentanol Amino Alcohol Escherichia coli Engineering Escherichia coli BL21(DE3) for the Production of 5-Amino-1-Pentanol