文献类型：期刊文献

英文题名：Insights into 3-hydroxypropionic acid biosynthesis revealed by overexpressing native glycerol dehydrogenase in Klebsiella pneumoniae

作者：Su, Ming-Yue[1];Li, Ying[1];Ge, Xi-Zhen[2];Tian, Ping-Fang[1]

第一作者：Su, Ming-Yue

通讯作者：Tian, PF[1]

机构：[1]Beijing Univ Chem Technol, Beijing Key Lab Bioproc, Coll Life Sci & Technol, Beijing 100029, Peoples R China;[2]Beijing Union Univ, Coll Biochem Engn, Beijing, Peoples R China

第一机构：Beijing Univ Chem Technol, Beijing Key Lab Bioproc, Coll Life Sci & Technol, Beijing 100029, Peoples R China

通讯机构：[1]corresponding author), Beijing Univ Chem Technol, Beijing Key Lab Bioproc, Coll Life Sci & Technol, Beijing 100029, Peoples R China.

年份：2014

卷号：28

期号：4

起止页码：762-768

外文期刊名：BIOTECHNOLOGY & BIOTECHNOLOGICAL EQUIPMENT

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000348934100025)】；

基金：This work was supported by National Natural Science Foundation of China [grant number 20876009], [grant number 21076013], [grant number 21276014]; National Basic Research Program of China (973 Program) [grant number 2012CB725200].

语种：英文

外文关键词：Klebsiella pneumoniae; glycerol dehydrogenase; overexpression; 3-Hydroxypropionic acid

摘要：In Klebsiella pneumoniae, glycerol dissimilation involves parallel oxidation and reduction pathways. Oxidation pathway provides adenosine triphosphate (ATP) and cofactors to sustain cell growth, while reduction pathway presents 3-hydroxypropionic acid (3-HP) and 1,3-propanediol(1,3-PDO), which are commercially attractive platform chemicals. Previous metabolic engineering of K. pneumoniae focused on the intensification of reduction pathway; however, it failed to overproduce 3-HP or 1,3-PDO. Contrary to this strategy, here we show that overexpression of glycerol dehydrogenase (dhaD), the first functional enzyme in oxidation pathway, can efficiently stimulate cell growth and facilitate 3-HP accumulation. Under microaerobic conditions, although metabolic burden arising from plasmid replication, the recombinant K. pneumoniae overexpressing dhaD grew actively and showed 60% enhancement of 3-HP compared to the control. In particular, overexpression of dhaD increased the activity of glycerol dehydratase, indicating the concerted action of two enzymes and the interdependence between glycerol oxidation and reduction pathways. Moreover, the strain overexpressing dhaD produced more lactic acid yet less acetic acid than the control, implying the interplay between dhaD expression and the formation of byproducts. Together, not only showing that intensifying glycerol oxidation pathway is beneficial to 3-HP production, this study also reveals the structural rigidity of dha operon that mediates glycerol dissimilation in K. pneumoniae.