Alkane and wax ester production from lignin‐related aromatic compounds

Abstract

Lignin has potential as a sustainable feedstock for microbial production of industrially relevant molecules. However, the required lignin depolymerization yields a heterogenic mixture of aromatic monomers that are challenging substrates for the microorganisms commonly used in the industry. Here, we investigated the properties of lignin-related aromatic compounds (LRAs), namely coumarate, ferulate, and caffeate, in the synthesis of biomass and products in an LRA-utilizing bacterial host Acinetobacter baylyi ADP1.The biosynthesis products, wax esters, and alkanes are relevant compounds for the chemical and fuel industries. Here, wax esters were produced by a native pathway of ADP1, whereas alkanes were produced by a synthetic pathway introduced to the host.Using individual LRAs as substrates, the growth and product formation were monitored with internal biosensors and off-line analytics. Of the tested LRAs, coumarate was the most propitious in terms of product synthesis. Wax esters were produced from coumarate with yield and titer of 37 mg/g coumarate and 202 mg/L, whereas alkanes were produced with a yield of 62.3 µg /g coumarate and titer of 152 µg/L. This study demonstrates the microbial preference for certain LRAs and highlights the potential of A. baylyi ADP1 as a host for LRA upgrading to value-added products. K E Y W O R D SAcinetobacter baylyi ADP1, alkane, lignin, wax ester

Towards bioproduction of poly-α-olefins from lignocellulose

“…[10][11][12][13][14] It is tolerant towards lignocellulose related monomeric compounds, such as phenolic acids, acetate, and ethanol, which typically inhibit microbial growth. [15][16][17][18] Furthermore, it can utilize monomeric lignin compounds through catabolic β-ketoadipate pathway, which efficiently funnels carbon to biomass and storage compound synthesis. 17,19,20 The Acinetobacter genera and A. baylyi ADP1 have also been identified with lignin depolymerizing activities.…”

“…[15][16][17][18] Furthermore, it can utilize monomeric lignin compounds through catabolic β-ketoadipate pathway, which efficiently funnels carbon to biomass and storage compound synthesis. 17,19,20 The Acinetobacter genera and A. baylyi ADP1 have also been identified with lignin depolymerizing activities. 21,22 Novel biorefineries are expected to produce large quantities of different types of technical lignins as a by-product.…”

Wax ester production in nitrogen-rich conditions by metabolically engineeredAcinetobacter baylyiADP1

“…The luminescence signals generated by the two strains were monitored during the cultivation; the cumulative luminescence can be used as an indicator to compare the amounts of fatty aldehyde produced by the two strains (Lehtinen et al, 2018a; Salmela et al, 2019; Santala et al, 2011a).…”

“…In addition, Acinetobacter baylyi ADP1, is an ideal cellular platform for synthetic biology and metabolic engineering due to its genetic tractability (de Berardinis et al, 2008; Metzgar, 2004; Murin et al, 2012; Suárez et al, 2017; Tumen-Velasquez et al, 2018), thus enabling it to be a suitable host to study storage lipid production (Santala et al, 2014). Besides WEs, A. baylyi ADP1 has also been engineered to produce various native and non-native oleochemicals, such as alkanes, alkenes, and triacylglycerols (Lehtinen et al, 2018b; Luo et al, 2019; Salmela et al, 2019; Santala et al, 2011b).…”

Enhanced Population Control in Synthetic Bacterial Consortium by Interconnected Carbon Cross-Feeding

“…In this study, our aim was to model and construct a synthetic consortium with an interconnected crossfeeding system that is solely based on the cooperative utilization of a single carbon source. We employed as hosts Escherichia coli K-12 and the soil bacterium Acinetobacter baylyi ADP1, which has been previously used both in synthetic microbial consortia (17,27,28) and in production of industrially relevant compounds from various substrates (29)(30)(31). In order to implement the cross-feeding between E. coli and A. baylyi ADP1, both strains were engineered to be incapable of glucose utilization alone.…”