AUTHOR=Burgardt Arthur , Prell Carina , Wendisch Volker F. 

TITLE=Utilization of a Wheat Sidestream for 5-Aminovalerate Production in Corynebacterium glutamicum

JOURNAL=Frontiers in Bioengineering and Biotechnology

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2021.732271

DOI=10.3389/fbioe.2021.732271

ISSN=2296-4185

ABSTRACT=<p>Production of plastics from petroleum-based raw materials extensively contributes to global pollution and CO<sub>2</sub> emissions. Biotechnological production of functionalized monomers can reduce the environmental impact, in particular when using industrial sidestreams as feedstocks. <italic>Corynebacterium glutamicum</italic>, which is used in the million-ton-scale amino acid production, has been engineered for sustainable production of polyamide monomers. In this study, wheat sidestream concentrate (WSC) from industrial starch production was utilized for production of <sc>l</sc>-lysine–derived bifunctional monomers using metabolically engineered <italic>C. glutamicum</italic> strains. Growth of <italic>C. glutamicum</italic> on WSC was observed and could be improved by hydrolysis of WSC. By heterologous expression of the genes <italic>xylA</italic><sub><italic>Xc</italic></sub><italic>B</italic><sub><italic>Cg</italic></sub> (<italic>xylA</italic> from <italic>Xanthomonas campestris</italic>) and <italic>araBAD</italic><sub><italic>Ec</italic></sub> from <italic>E. coli</italic>, xylose, and arabinose in WSC hydrolysate (WSCH), in addition to glucose, could be consumed, and production of <sc>l</sc>-lysine could be increased. WSCH-based production of cadaverine and 5-aminovalerate (5AVA) was enabled. To this end, the lysine decarboxylase gene <italic>ldcC</italic><sub><italic>Ec</italic></sub> from <italic>E. coli</italic> was expressed alone or for conversion to 5AVA cascaded either with putrescine transaminase and dehydrogenase genes <italic>patDA</italic><sub><italic>Ec</italic></sub> from <italic>E. coli</italic> or with putrescine oxidase gene <italic>puo</italic><sub><italic>Rq</italic></sub> from <italic>Rhodococcus qingshengii</italic> and <italic>patD</italic><sub><italic>Ec</italic></sub>. Deletion of the <sc>l</sc>-glutamate dehydrogenase–encoding gene <italic>gdh</italic> reduced formation of <sc>l</sc>-glutamate as a side product for strains with either of the cascades. Since the former cascade (<italic>ldcC</italic><sub><italic>Ec</italic></sub>-<italic>patDA</italic><sub><italic>Ec</italic></sub>) yields <sc>l</sc>-glutamate, 5AVA production is coupled to growth by flux enforcement resulting in the highest 5AVA titer obtained with WSCH-based media.</p>