Tailored Synthesis of Poly([R]-3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB/HV) inRalstonia eutropha DSM 428

摘要: Ralstonia eutropha was grown in a chemostat at dilution rate of D = 0.1 ′ 0.01 h - 1 under the conditions simultaneous limitation by carbon (butyric and/or valeric acid) and nitrogen (ammonium). In order to achieve aphysiological state with high cellular polyhydroxyalkanoate (PHA) content, ratio total feed medium kept constant 17 mol C/mol N only butyric acid varied feed. When fed, poly([R]-3-hydroxybutyrate) (PHB) isolated. For substrate mixtures consisting acid, alone, co-polymer poly([R]-3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB/HV) incorporated maximum content (R)-3-hydroxyvalerate 62 mol%. The melting temperature PHA decreased from 178 °C for PHB about 80 highest HV content. molecular weight (M w ) polymer between 0.9 1.2 × 10 6 polydispersity 3 0.3. composition cells non-linear function mixture. It concluded that dual (C, N) limited growth cultures could be used tailor PHB/HV an accurate way, which is not possible when using batch cultures.