%0 Journal Article
%T Manipulation of Carbon flux in S. cerevisiae to improve L-lactic acid production<br>双层面调控S. cerevisiae碳流促进L-乳酸积累
%A Liangliang Zhao
%A Jun Wang
%A Jingwen Zhou
%A Liming Liu
%A Guocheng Du
%A Jian Chen
%A <br>赵亮亮
%A 汪军
%A 周景文
%A 刘立明
%A 堵国成
%A 陈坚
%J 微生物学报
%D 2011
%I 
%X Abstract: Objective] The target of this study was to develop an engineered Sacchromyces cerevisiae strain to produce L-lactic acid efficiently using glucose as carbon source. Methods] For construction of the strain CEN.PK2-1CLDH], we integrated a LDH gene coding L-lactic acid dehydrogenase from Bovine into the genome of S. cerevisiae via homologous recombination and meanwhile knocked out a PDC1 gene coding pyruvate decarboxylase. As this, the carbon fluxes were led into L-Lactic acid. On the basis, we analyzed the Km value of these key enzymes to NADH and successfully over-expressed a NADH oxidase (nox) from Streptococcus pneumoniae into the cytoplasm for the construction of S. cerevisiae CEN.PK2-1CLDH]-nox. Results] Compared to initial strain, the yield of L-lactic acid in CEN.PK2-1CLDH] fermentation liquor increased from 0 g/L to 15 g/L and the concentration of ethanol decreased from 27.3 g/L to 16.2 g/L. Furthermore, the concentration of L-lactic acid increased further to 20 g/L and the concentration of ethanol decreased to 8.2 g/L. Conclusions] The results indicated that carbon metabolic flux was redistributed to efficient accumulation of L-lactic acid through two-sided control that heterologous expression of the gene LDH and decreasing the ratio of NADH/NAD+.
%K Keywords: Saccharomyces cerevisiae
%K L-lactic acid
%K carbon flux
%K NADH<br>关键词：S.
%K cerevisiae，L-乳酸，碳代谢流，NADH
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=A3C6BA55AB623B90FA9104CFFC826F3C&aid=5C91380F9EBFD4FA04554A0D0DC53971&yid=9377ED8094509821&vid=987EDA49D8A7A635&iid=CA4FD0336C81A37A&sid=771152D1ADC1C0EB&eid=9FFCC7AF50CAEBF7&journal_id=0001-6209&journal_name=微生物学报&referenced_num=1&reference_num=46