Detection and cloning of 1,3-propanediol biosynthesis genes from glycerol in Klebsiella pneumoniae GLC29.

Author(s)

Amanda Billia Flora

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2015-11-24

Examining board members

José Gregorio Cabrera Gomez; Mário Henrique de Barros; Rodrigo da Silva Galhardo; Gabriel Padilla Maldonado; Marilis do Valle Marques

• Advisor: José Gregorio Cabrera Gomez

Abstract

The 1,3-propanediol is a compound produced from glycerol fermentation by bacteria such as Klebsiella and which can be used for various applications in industry, such as the production of PTT (polytrimethylene terephthalate). This work focused on the production of 1,3-propanediol using genes encoding the enzymes of the pathway taken from a Klebsiella strain previously isolated (GLC29). The genes were inserted into a plasmid and in the host strain of Escherichia coli with changes in the affinity of the enzyme isocitrate dehydrogenase for its cofactor. The enzyme was modified in the genome of the bacteria using the cofactor NAD instead of the original NADP. Preliminary tests on shaker showed an improvement of production by the mutated strains in comparison to the wild Escherichia coli. In biorreactor cultivation, varying the concentration of dissolved oxygen in the medium, the mutant strain showed a production 25% higher than the wild type strain in the condition with 5% of dissolved oxygen. (AU)

• FAPESP's process: 12/14552-2 - Detection and cloning of biosynthesis genes of 1,3-propanediol from glycerol in Klebsiella pneumoniae GLC29
• Grantee: Amanda Billia Flora
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)