| The vgb gene coding for Vitreoscilla Hemoglobin was transferred into wild type strain K.oxytoca M5al, also the fdh gene coding for formate dehydrogenase and vgb were transferred into K.oxytoca M5al together. Then the influnce of heterogeneous proteins on the fementation of 1,3-propanediol was studied. The results were shown as followed:We found that domestication of strain could obviously enhance the production of 1,3-propanediol. After domestication the cell growth was better than undomesticated strain, fermentation broth domestication had more influence on glycerol consumption and 1,3-propanediol production as well as on cell growth. After 45 hours'fermentation, the yield of 1,3-propanediol of glycerol domesticated strain and fermentation broth domesticated strain were 6.58 g·l-1 and 7.36 g·l-1,respectively. Compared with the wild type strain, the production of 1,3-propanediol was enhanced 41.2% and 57.94%,respectively. it stated clearly that fermentation broth domestication could not only enhance the endurence of substrate glycerol, but also enhanced endurence of products such as 1,3-propanediol, ethanol, lactate. So finally it could enhance the productivity of 1,3-propanediol.The result of shaking flask fermentation under differents dissoved oxygen conditions showed that dissoved oxygen was a main factor that influnced the fermentation results, 500ml flask filled with 100ml medium would be the best dissoved oxygen condition, and the final concentration of 1,3-propanediol of 11.2g·l-1 was gained in this condition.Vitreoscilla Hemoglobin and formate dehydrogenase were successfully expressed in K.oxytoca M5al, CO bonding experiment and formate dehydrogenase enzyme activity analysis showed that those heterogeneous proteins had fuctional activity. Recombinent plasmids pDV and pDFV were constructed which contained parDE gene, compared with plasmid pV or pFV, the stability of plasmid in recombinant strains contained parDE were obviously enhanced. Continuous passage 48 hours, only 23.3%,39.1% of plasmid pDV and pDFV were lost, while about 69.6%,79.3% of plasmid pV and pFV were lost. And it showed that the FDH activity were also less lost because of parDE gene.The 1,3-PD production of recombinant strain M5al-pDV was higher than wild strain M5al while biomass was lower than M5al. Under high dissolved oxygen condition, after 45 hours, the yields of 1,3-PD of M5al and M5al-pDV were 9.27 g l-1 and 11.15 g l-1, respectively. The production of 1,3-PD of recombinant strain was 20.28% higher, and the ethanol also increased while the lactate concentration decreased. Under low dissolved oxygen condition, after 45 hours, the yields of 1,3-PD of M5al and M5al-pV were 6.4 g l-1 and 9.2 g l-1, respectively. The production of 1,3-PD of recombinant strain was 43.7% higher, and both lactate and ethanol concentrations decreased.Recombinant strain M5al-pDFV was constructed which contain both Vitreoscilla Hemoglobin and formate dehydrogenase. After 45 hours'fermentation, the yields of 1,3-PD was 12.4 g·l-1,the production of 1,3-PD of M5al-pDFV was 93.75% higher compared with wild strain. The concentration of NADH in recobminent M5al-pDV,M5al-pDFV biomass were higher than wild strian, this may be the reason why the 1,3-PD production of recombinent strains increased.
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