Fig. 2: Integrating demethylation genes to endow R. eutropha H16 with the ability to metabolize vanillic acid.
From: Lignin valorization to bioplastics with an aromatic hub metabolite-based autoregulation system
a Schematic illustration of the conversion of VA to PCA catalyzed by demethylation genes from different sources. b H16PM-1 (R. eutropha H16 harboring PM-1: Plac: ligM) cultivated in minimal medium supplemented with vanillic acid. c Growth and metabolism of H16PM-6 (R. eutropha H16 harboring PM-6: Plac: ligM-ligH-metF) with added cofactor regeneration modules in minimal medium supplemented with vanillic acid. The genes ligH and metF were involved in the regeneration of tetrahydrofolate in Sphingomonas sp. SYK-6. d H16PAB-1 (R. eutropha H16 harboring Plac: vanAB) cultivated in minimal medium supplemented with vanillic acid. e H16PABA (R. eutropha H16 harboring Plac: vanAB-fdhA) with an added formaldehyde detoxification module was cultured in minimal medium with VA as the sole carbon source. f Differences in formate dehydrogenase transcript levels in H16PABA (R. eutropha H16 harboring Plac: vanAB-fdhA) when metabolizing vanillic acid and protocatechuic acid. Change in formate dehydrogenase transcript levels when H16PABA metabolized VA (dark blue) and the transcript level of formate dehydrogenase when PCA was metabolized as a control (light blue). PCA protocatechuic acid, VA vanillic acid, OD600nm optical density, measured as absorbance at 600 nm. Error bars illustrate the standard deviation of three biological replicates. The data are the mean ± SD, n = 3, unpaired two-tailed t test. Source data are provided as a Source Data file.
