Metabolic engineering of cobalamin (vitamin B12) production in Bacillus megaterium.
Metabolic engineering of cobalamin (vitamin B12) production in Bacillus megaterium.
复制标题
钴胺的代谢工程（维生素B12）生产中的芽孢杆菌。
DOI：
10.1111/j.1751-7915.2009.00125.x
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发表时间：
2010-01
影响因子：
5.7
通讯作者：
Jahn D
中科院分区：
文献类型：
--
作者：
Biedendieck R;Malten M;Barg H;Bunk B;Martens JH;Deery E;Leech H;Warren MJ;Jahn D
巨大芽孢杆菌中钴胺素（维生素B12）的生产已成为系统评价单一和多重定向分子和遗传优化策略的模型系统。基于质粒和基因组的维生素B12生物合成相关基因的过表达，包括cbiX，sirA，修饰的hemA，操纵子hemAXCDBL和cbiXJCDETFGAcysGAcbiYbtuR，以及调控基因fnr，显着增加钴胺素的产量。为了减少沿着四吡咯途径的血红素分支的通量，成功地采用了涉及编码粪卟啉原III氧化酶的hemZ基因沉默的反义RNA策略。反馈抑制的初始酶的四吡咯生物合成，血红素，血红素被克服了稳定的酶过量生产。类似地，去除cbiXJCDETLFGAcysGAcbiYbtuRoperon上游的B12核糖开关和重组产生三种不同的维生素B12结合蛋白（谷氨酸盐GlmS，核糖核苷酸三磷酸还原酶RtpR和甲硫氨酸合成酶MetH）部分消除了B12依赖性反馈抑制。所有这些策略都增加了B中钴胺素的产量。巨大的最后，这些策略的组合提高了整体细胞内维生素B12的浓度，但也降低了体积细胞量，通过将生物体置于代谢应激下。
Cobalamin (vitamin B12) production in Bacillus megaterium has served as a model system for the systematic evaluation of single and multiple directed molecular and genetic optimization strategies. Plasmid and genome‐based overexpression of genes involved in vitamin B12 biosynthesis, including cbiX, sirA, modified hemA, the operons hemAXCDBL and cbiXJCDETLFGAcysGAcbiYbtuR,and the regulatory gene fnr, significantly increased cobalamin production. To reduce flux along the heme branch of the tetrapyrrole pathway, an antisense RNA strategy involving silencing of the hemZ gene encoding coproporphyrinogen III oxidase was successfully employed. Feedback inhibition of the initial enzyme of the tetrapyrrole biosynthesis, HemA, by heme was overcome by stabilized enzyme overproduction. Similarly, the removal of the B12 riboswitch upstream of the cbiXJCDETLFGAcysGAcbiYbtuRoperon and the recombinant production of three different vitamin B12 binding proteins (glutamate mutase GlmS, ribonucleotide triphosphate reductase RtpR and methionine synthase MetH) partly abolished B12‐dependent feedback inhibition. All these strategies increased cobalamin production in B. megaterium. Finally, combinations of these strategies enhanced the overall intracellular vitamin B12 concentrations but also reduced the volumetric cellular amounts by placing the organism under metabolic stress.
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影响因子：
2.9
作者：
Chen, DW;Abend, A;Frey, PA
通讯作者：
Frey, PA
影响因子：
56.9
作者：
DRENNAN, CL;HUANG, S;LUDWIG, ML
通讯作者：
LUDWIG, ML
影响因子：
16.6
作者：
BLANCHE, F;THIBAUT, D;MULLER, G
通讯作者：
MULLER, G
影响因子：
64.8
作者：
Croft, MT;Lawrence, AD;Smith, AG
通讯作者：
Smith, AG
影响因子：
4.1
作者：
Beine, Rafael;Moraru, Roxana;Seibel, Juergen
通讯作者：
Seibel, Juergen