title: Development of recombinant Klebsiella pneumoniae ∆dhaT strain for the co-production of 3-hydroxypropionic acid and 1,3-propanediol from glycerol.
abstract: Klebsiella pneumoniae converts glycerol to the specialty chemical 1,3-propanediol (1,3-PDO), which is used for the production of polytrimethylene terepthalate (PTT). In this study, an NAD(+)-dependent gamma-glutamyl-gamma-aminobutyraldehyde dehydrogenase (PuuC) of K. pneumoniae DSM 2026, which oxidizes 3-hydroxypropionaldehyde to a platform chemical 3-hydroxypropionic acid (3-HP), was cloned and overexpressed in K. pneumoniae DSM 2026 for the co-production of 3-HP and 1,3-PDO from glycerol. In addition, the gene dhaT, encoding NADH-dependent 1,3-propanediol oxidoreductase (1,3-PDOR), was deleted from the chromosome for the balanced production of 3-HP and 1,3-PDO. The recombinant K. pneumoniae ∆dhaT, expressing puuC, produced 3.6 g 3-HP and 3.0 g 1,3-PDO per liter with an average yield of 81% on glycerol carbon in shake flask culture under microaerobic conditions. When a fed-batch culture was carried out under microaerobic conditions at pH 7.0 in a 5-l bioreactor, the recombinant K. pneumoniae ∆dhaT (puuC) strain produced 16.0 g 3-HP and 16.8 g 1,3-PDO per liter with a cumulative yield of 51% on glycerol carbon in 24 h. The production of 1,3-PDO in the dhaT-deletion mutant was attributed to the expression of NAD(P)H-dependent hypothetical oxidoreductase. This study demonstrates the feasibility of obtaining two commercially valuable chemicals, 3-HP and 1,3-PDO, at a significant scale.
authors.affiliation: Department of Chemical and Biomolecular Engineering, International Affairs, Pusan National University, Busan, South Korea.
authors.forename: Somasundar
authors.initials: S
authors.lastname: Ashok
authors.forename: Subramanian Mohan
authors.initials: SM
authors.lastname: Raj
authors.forename: Chelladurai
authors.initials: C
authors.lastname: Rathnasingh
authors.forename: Sunghoon
authors.initials: S
authors.lastname: Park
mesh_terms: D000426:Alcohol Dehydrogenase / Q000235:genetics* / Q000378:metabolism; D000445:Aldehyde Oxidoreductases / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D017353:Gene Deletion; D005818:Genetic Engineering; D005990:Glycerol / Q000378:metabolism*; D007711:Klebsiella pneumoniae / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D019344:Lactic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D011409:Propylene Glycols / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D011409:Propylene Glycols; D019344:Lactic Acid; C041787:1,3-propanediol; C031601:hydracrylic acid; D000426:Alcohol Dehydrogenase; C052370:1,3-propanediol dehydrogenase; D000445:Aldehyde Oxidoreductases; C019679:aminobutyraldehyde dehydrogenase; D005990:Glycerol