Engineering a pyridoxal 5'-phosphate supply for cadaverine production by using Escherichia coli whole-cell biocatalysis.

Content Provider	Europe PMC
Author	Ma, Weichao Cao, Weijia Zhang, Bowen Chen, Kequan Liu, Quanzhen Li, Yan Ouyang, Pingkai
Copyright Year	2015
Abstract	Although the routes of de novo pyridoxal 5'-phosphate (PLP) biosynthesis have been well described, studies of the engineering of an intracellular PLP supply are limited, and the effects of cellular PLP levels on PLP-dependent enzyme-based whole-cell biocatalyst activity have not been described. To investigate the effects of PLP cofactor availability on whole-cell biocatalysis, the ribose 5-phosphate (R5P)-dependent pathway genes pdxS and pdxT of Bacillus subtilis were introduced into the lysine decarboxylase (CadA)-overexpressing Escherichia coli strain BL-CadA. This strain was then used as a whole-cell biocatalyst for cadaverine production from L-lysine. Co-expression strategies were evaluated, and the culture medium was optimised to improve the biocatalyst performance. As a result, the intracellular PLP concentration reached 1144 nmol/gDCW, and a specific cadaverine productivity of 25 g/gDCW/h was achieved; these values were 2.4-fold and 2.9-fold higher than those of unmodified BL-CadA, respectively. Additionally, the resulting strain AST3 showed a cadaverine titre (p = 0.143, α = 0.05) similar to that of the BL-CadA strain with the addition of 0.1 mM PLP. These approaches for improving intracellular PLP levels to enhance whole-cell lysine bioconversion activity show great promise for the engineering of a PLP cofactor to optimise whole-cell biocatalysis.
Journal	Scientific Reports [Sci Rep]
Volume Number	5
DOI	10.1038/srep15630
PubMed Central reference number	PMC4614675
PubMed reference number	26490441
e-ISSN	20452322
Language	English
Publisher	Nature Publishing Group
Publisher Date	2015-10-22
Access Restriction	Open
Content Type	Text
Resource Type	Article
Subject	Multidisciplinary