Metabolic engineering of microorganisms for production of aromatic compounds

Abstract

Metabolic engineering has been enabling development of high performance microbial strains for the efficient production of natural and non-natural compounds from renewable non-food biomass. Even though microbial production of various chemicals has successfully been conducted and commercialized, there are still numerous chemicals and materials that await their efficient bio-based production. Aromatic chemicals, which are typically derived from benzene, toluene and xylene in petroleum industry, have been used in large amounts in various industries. Over the last three decades, many metabolically engineered microorganisms have been developed for the bio-based production of aromatic chemicals, many of which are derived from aromatic amino acid pathways. This review highlights the latest metabolic engineering strategies and tools applied to the biosynthesis of aromatic chemicals, many derived from shikimate and aromatic amino acids, including l -phenylalanine, l -tyrosine and l -tryptophan. It is expected that more and more engineered microorganisms capable of efficiently producing aromatic chemicals will be developed toward their industrial-scale production from renewable biomass.

Harnessing evolutionary diversification of primary metabolism for plant synthetic biology

“…Microbial metabolic engineering and synthetic biology studies demonstrated that redirection of carbon flux and efficient supply of a specific primary precursor(s) are critical to achieve efficient production of downstream target products ( Fig. 1A) (16,(35)(36)(37)(38). Thus, holistic understanding and engineering of both primary and specialized metabolisms are crucial for efficient and sizable production of natural products in plants.…”

Genetic engineering approaches for the fermentative production of phenylglycines

“…Furthermore, it is important to mention that, unlike the studies in E. coli, the precursor supply of phenylpyruvate was not modified in our strains. This is a pivotal target for further studies as usually the aromatic amino acid biosynthesis pathway in bacteria is strictly regulated and limits the precursor supply (Huccetogullari et al 2019;Lee and Wendisch 2017;Rodriguez et al 2014;Sprenger 2007). It was shown for Streptomyces venezuelae that an improved flux through the shikimate pathway by overexpressing the genes of shikimate kinase (aroK) and dehydroquinate synthase (aroB) increased the production of the aromatic antibiotic chloramphenicol (Vitayakritsirikul et al 2016).…”

Strategies for the production of biochemicals in bioenergy crops

“…The shikimate pathway, which is confined to plastids in plants, is responsible for the synthesis of aromatic amino acids that are precursors to secondary metabolites such as pigments, alkaloids, hormones, and phenylpropanoids including lignin [9]. In microbes, the shikimate pathway has been exploited for the production of aromatic chemicals which are otherwise derived from petroleum-based benzene, toluene and xylene [10,11]. Nevertheless, most aromatic compounds used for industrial applications are still synthesized chemically Fig.…”