Expression of Vitreoscilla Hemoglobin Enhances Cell Growth and Dihydroxyacetone Production in Gluconobacter oxydans
Expression of Vitreoscilla Hemoglobin Enhances Cell Growth and Dihydroxyacetone Production in Gluconobacter oxydans
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DOI：
10.1007/s00284-010-9621-6
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发表时间：
2010-11-01
影响因子：
2.6
通讯作者：
Wei, Dongzhi
中科院分区：
文献类型：
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作者：
Li, Minghua;Wu, Jian;Wei, Dongzhi
二羟基丙酮（DHA）是一种重要的酮类糖，广泛应用于化妆品、化工、医药等行业。DHA是由氧需求量大的氧化葡萄糖杆菌工业化生产的。为了提高DHA的产量，我们成功地将编码玻璃体颤菌血红蛋白（VHb）的基因vgb引入到g.o oxidans中，使其稳定表达，并以约76.0 nmol/g干细胞重的速度表达。结果表明，在不同的曝气条件下，组成型表达的VHb促进了氧化虾细胞的生长和DHA的产生。特别是在低曝气量条件下，在生物反应器中发酵32 h后，表达VHb的菌株（VHb(+)）的生物量比不表达VHb的菌株（VHb（-)）高23.13%，DHA产量比不表达VHb(-)）高37.36%。此外，在发酵过程中，VHb（+）菌株的摄氧量（OUR）也相对于对照菌株有所增加。
Dihydroxyacetone (DHA) is an important ketose sugar, which is extensively used in the cosmetic, chemical, and pharmaceutical industries. DHA has been industrially produced by Gluconobacter oxydans with a high demand of oxygen. To improve the production of DHA, the gene vgb encoding Vitreoscilla hemoglobin (VHb) was successfully introduced into G. oxydans, where it was stably maintained, and expressed at about 76.0 nmol/g dry cell weight. Results indicated that the constitutively expressed VHb improved cell growth and DHA production in G. oxydans under different aeration conditions. Especially at low aeration rates, the VHb-expressing strain (VHb(+)) displayed 23.13% more biomass and 37.36% more DHA production than those of VHb-free strain (VHb(-)) after 32 h fermentation in bioreactors. In addition, oxygen uptake rate (OUR) was also increased in VHb(+) strain relative to the control strain during fermentation processes.