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J Ind Microbiol Biotechnol (2014) 41:14431450 DOI 10.1007/s10295-014-1476-6
METABOLIC ENGINEERING AND SYNTHETIC BIOLOGY
Received: 31 March 2014 / Accepted: 16 June 2014 / Published online: 6 July 2014 Society for Industrial Microbiology and Biotechnology 2014
metabolites [4]. In addition, L-serine is also a predominant source of one-carbon units used for a number of anabolic processes [5].
The current L-serine production relies mainly on enzymatic or cellular conversion method. Using a hydroxymethyltransferase, L-serine could be produced enzymatically from glycine and formaldehyde [6]. Employing the resting cells of methanol-utilizing bacteria Hyphomicrobium methylovorum, L-serine production was obtained using glycine and methanol as substrate with a yield of 24 g/L [7]. Although high L-serine production was achieved in these systems, the dependence on expensive substrates and low productivity make them less attractive. Meanwhile, fermentative production of L-serine from glucose received less attention due to its complicated regulation network in vivo as a central intermediate for a number of cellular reactions. In 2005, Peters-Wendisch et al. [8] constructed an L-serine producing Corynebacterium glutamicum strain by deleting L-serine dehydratase gene, reducing expression of the serine hydroxymethyltransferase, and overex-pressing the L-serine biosynthetic genes serA, serC, and serB. This strain produced 9.04 g/L L-serine directly from glucose. Later, to reduce availability of 5,6,7,8-tetrahydrofolate and control the activity of hydroxymethyltransferase, Stolz et al. [5] knocked out pabABC genes in C. glutamicum, and further increased L-serine production to 36.26 g/L in 20-L fed-batch fermentation. In addition, by blocking or attenuating the degradation of L-serine, releasing the feedback inhibition of 3-phosphoglycerate dehydrogenase, and co-expression of 3-phosphoglycerate kinase and feedback-resistant 3-phosphoglycerate dehydrogenase in C. glutamicum ATCC 13032, Lai et al. [2] also obtained a recombinant strain SER-8.
As a host, E. coli has also been widely used in the synthesis of amino acids due to its clear genetic background
Construction of an l-serine producing Escherichia coli via metabolic engineering
Pengfei Gu Fan Yang Tianyuan Su Fangfang Li Yikui Li Qingsheng Qi
Abstract L-Serine is a nonessential amino acid, but plays a crucial role as a building block for cell growth. Currently,
L-serine production is mainly dependent on enzymatic or cellular conversion. In this study, we constructed a recombinant Escherichia coli that can fermentatively produce
L-serine from glucose. To accumulate L-serine, sdaA encoding the L-serine dehydratase, iclR encoding...