title: Co-production of 3-hydroxypropionic acid and 1,3-propanediol by Klebseilla pneumoniae expressing aldH under microaerobic conditions.
abstract: Fed-batch cultures of Klebsiella pneumoniae expressing Escherichia coli aldH were performed under microaerobic conditions to investigate the effects on metabolites production. Increasing the aeration rate enhanced cell growth and 3-hydroxypropionic acid (3-HP) production, but reduced 1,3-propanediol (1,3-PDO) formation. The recombinant strain K. pneumoniae/pUC18kan-aldHec produced 48.9 g/L of 3-HP and 25.3g/L of 1,3-PDO with an overall yield of 0.66 mol/mol in 28 h at an aeration rate of 1.5 vvm; however, under fully aerobic condition, no 3-HP and 1,3-PDO were produced due to the repression of dha operon. The flux through the reaction catalyzed by glycerol dehydratase and the split ratio of 1,3-PDO were negatively correlated with the aeration rate, even though the 3-HP level showed a positive trend. This study demonstrated that the relative amounts of 3-HP and 1,3-PDO can be controlled by the aeration rate.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Yanna
authors.initials: Y
authors.lastname: Huang
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Li
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Shimizu
authors.forename: Qin
authors.initials: Q
authors.lastname: Ye
mesh_terms: D000332:Aerobiosis / Q000502:physiology; D000445:Aldehyde Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D061249:Batch Cell Culture Techniques / Q000379:methods*; D019149:Bioreactors / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000235:genetics / Q000378:metabolism*; D019344:Lactic Acid / Q000031:analogs & derivatives* / Q000096:biosynthesis; D010100:Oxygen / Q000378:metabolism*; D011409:Propylene Glycols / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D011409:Propylene Glycols; D011994:Recombinant Proteins; D019344:Lactic Acid; C041787:1,3-propanediol; C031601:hydracrylic acid; C575020:4,4'-diaponeurosporen-aldehyde dehydrogenase, Staphylococcus aureus; D000445:Aldehyde Oxidoreductases; D010100:Oxygen