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

• Grant number: 12/14552-2
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: October 01, 2012
• End date: August 31, 2015
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: José Gregório Cabrera Gomez
• Grantee: Amanda Billia Flora
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Nowadays, petroleum is main utilized energetic source, however with its depletion, new energetic sources are been developed to replace it, as an example we have biodiesel, made from vegetable oils. In the biodiesel making process there is production of glycerol, that can be used as carbon source for fermentative processes as the one that produces 1,3-propanediol. 1,3-propanediol is a high priced molecule that can be recycled and is used in the industry as component in solvents, lubricants and in the production of PTT (polytrimethylene terephthalate). Many microorganisms can produce 1,3-propanediol from glycerol, and this occurs while using the pathway encoded by the dha genes. The study of these genes is necessary to increase and improve the diol production. This work had success in characterizing the genes that are responsible for the production of 1,3-propanediol from glycerol by Klebsiella pneumoniae GLC29 strain, previously isolated by Silva (2010), with PCR technique using primers designed to each cluster gene. Recombinant E. coli were obtained by insertion of the dha cluster. Using experimental data obtained from K. pneumoniae GLC29 and a metabolic network, developed in this study, metabolic elementary modes were indentified showing ways to improve the production of 1,3-propanodiol. This changes in the metabolism are obtained by the transformation of the affinity of glycerol catabolism enzymes or 1,3-propanediol biosynthesis enzymes for reduced coenzymes (NAD+/NADH - NADP+/NADPH) and can lead to an increase of the 1,3-propanediol yield from glycerol from 0,55 g/g (data from cultures made by Silva, 2010) to 0,71 g/g, corresponding to the theoretical maximum. It is proposed in this work the construction/utilization of E. coli mutants containing enzymes modified in the specificity for coenzymes (NAD+/NADH versus NADP+/NADPH) in the construction of recombinant strains producing 1,3-propanediol. (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

FLORA, Amanda Billia. Detection and cloning of 1,3-propanediol biosynthesis genes from glycerol in Klebsiella pneumoniae GLC29.. 2015. Doctoral Thesis - Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI) São Paulo.