Microbial degradation of lignin and its related aromatic compounds has great potential for the sustainable production of chemicals and bioremediation of contaminated soils. We previously isolated sp. strain 9.1 from historical waste deposits (forming so-called fiber banks) released from pulp and paper mills along the Baltic Sea coast. The strain accumulated vanillyl alcohol during growth on vanillin, and while reported in other microbes, this phenotype is less common in wild-type pseudomonads. As the reduction of vanillin to vanillyl alcohol is an undesired trait in strains engineered to accumulate vanillin, connecting the strain 9.1 phenotype with a genotype would increase the fundamental understanding and genetic engineering potential of microbial vanillin metabolism. The genome of sp. 9.1 was sequenced and assembled. Annotation identified oxidoreductases with homology to alcohol dehydrogenase ADH6p, known to reduce vanillin to vanillyl alcohol, in both the 9.1 genome and the model strain KT2440. Recombinant expression of the sp. 9.1 FEZ21_09870 and KT2440 PP_2426 () genes in revealed that these open reading frames encode aldehyde reductases that convert vanillin to vanillyl alcohol, and that KT2440 PP_3839 encodes a coniferyl alcohol dehydrogenase that oxidizes coniferyl alcohol to coniferyl aldehyde (i.e., the function previously assigned to ). The deletion of PP_2426 in GN442 engineered to accumulate vanillin resulted in a decrease in by-product (vanillyl alcohol) yield from 17% to ∼1%. Based on these results, we propose the reannotation of PP_2426 and FEZ21_09870 as and PP_3839 as Valorization of lignocellulose (nonedible plant matter) is of key interest for the sustainable production of chemicals from renewable resources. Lignin, one of the main constituents of lignocellulose, is a heterogeneous aromatic biopolymer that can be chemically depolymerized into a heterogeneous mixture of aromatic building blocks; those can be further converted by certain microbes into value-added aromatic chemicals, e.g., the flavoring agent vanillin. We previously isolated a sp. strain with the (for the genus) unusual trait of vanillyl alcohol production during growth on vanillin. Whole-genome sequencing of the isolate led to the identification of a vanillin reductase candidate gene whose deletion in a recombinant vanillin-accumulating strain almost completely alleviated the undesired vanillyl alcohol by-product yield. These results represent an important step toward biotechnological production of vanillin from lignin using bacterial cell factories.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7054097 | PMC |
http://dx.doi.org/10.1128/AEM.02442-19 | DOI Listing |
Heliyon
November 2024
Saint Joseph University of Beirut, Faculty of Pharmacy, Department of Nutrition, Medical Sciences Campus, Damascus Road, P.O.B. 11-5076, Riad Solh Beirut, 1107 2180, Lebanon.
Olive mill wastewater (OMWW), a pollutant resulting from the olive oil industry, poses a serious ecological challenge due to its high pollution load. This effluent is highly concentrated in chemical oxygen demand (COD), which is 200 times higher than that of sewage wastewater. Moreover, OMWW is characterized by a strong acidity, high content of fatty matter, and high concentration of phenolic compounds.
View Article and Find Full Text PDFArch Biochem Biophys
November 2024
Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy. Electronic address:
The vanillyl alcohol oxidase/p-cresol methylhydroxylase (VAO/PCMH) flavoprotein family comprises a broad spectrum of enzymes capable of catalyzing the oxidative bioconversions of various substrates. Among them, pinoresinol hydroxylase (PinH) from the 4-alkylphenol oxidizing subgroup initiates the oxidative degradation of (+)-pinoresinol, a lignan important for both lignin structure and plant defense. In this study, we present a detailed biochemical and structural characterization of PinH from Pseudomonas sp.
View Article and Find Full Text PDFFood Chem
February 2025
Université de Lorraine, Laboratoire Ingénierie des Biomolécules (LIBio), 2 av. de la Forêt d'Haye, TSA 40602, 54518 Vandoeuvre Cedex, France. Electronic address:
This study hypothesizes that the solvent-free alcoholysis of oil recovered from salmon heads using vanillyl alcohol (VA) and immobilized lipase B can efficiently produce esters with enhanced stability and antioxidant properties. The objective was to investigate the selectivity and resulting ester profile, which may provide nutritional and functional advantages compared to supplementing oil with vanillyl alcohol. After 24 h, nearly complete conversion of vanillyl alcohol was achieved, leading to the production of various esters reflective of the oil's original fatty acid composition.
View Article and Find Full Text PDFFront Bioeng Biotechnol
October 2024
CSIR-Central Institute of Medicinal and Aromatic Plants (CIMAP), Lucknow, Uttar Pradesh, India.
The flavor of vanilla is a complex blend of compounds, with vanillin as the most prominent, along with vanillyl alcohol and 4-hydroxybenzoic acid. Natural vanillin extracted from vanilla beans is expensive, so researchers use heterologous synthesis to produce nature-identical vanillin in plant hosts. Consequently, alternative traditional farming and gathering methods are required to bridge the significant disparity between supply and demand.
View Article and Find Full Text PDFChem Asian J
December 2024
Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.
An optimised synthesis of the metal-organic framework (MOF) UiO-66(Ce) is reported using a modulator-free route, yielding ~5 g of material with high crystallinity and 22 % ligand defect. Two methods are developed for loading gold nanoparticles onto the MOF. The first uses a double-solvent method to introduce HAuCl onto UiO-66(Ce), followed by reduction under 5 % H in N, while the second is a novel one-pot method where HAuCl is added to the synthesis mixture, forming Au nanoparticles within the pores of the UiO-66(Ce) during crystallisation.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!