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Johnsen, Josefin

Publications and source records attributed to Johnsen, Josefin.

13 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

pACB108

plasmid used in https://www.osti.gov/biblio/2404295

Adaptive laboratory evolution↗
DOE OSTI2026

pACB109

plasmid used in https://www.osti.gov/biblio/2404295

Adaptive laboratory evolution↗
DOE OSTI2026

pACB110

plasmid used in https://www.osti.gov/biblio/2404295

Adaptive laboratory evolution↗
DOE OSTI2026

pACB111

plasmid used in https://www.osti.gov/biblio/2404295

Adaptive laboratory evolution↗
DOE OSTI2026

pACB112

For recombinant expression of fghA (PP_1617 from Pseudomonas putida) with the S11R mutation and a C-terminal His tag

Adaptive laboratory evolution↗
DOE OSTI2026

pACB113

For recombinant expression of fghA (PP_1617 from Pseudomonas putida) with the W15C mutation and a C-terminal His tag

Adaptive laboratory evolution↗
DOE OSTI2026

pACB120

For recombinant expression of fghA (PP_1617 from Pseudomonas putida) with five mutations (K10N, S11R, W15C, G76V, G258D) and a C-terminal His tag

Adaptive laboratory evolution↗
DOE OSTI2026

pACB143

For recombinant expression of vanB (PP_3737 from Pseudomonas putida) with the A24P mutation and an N-terminal thrombin-cleavable His tag

Adaptive laboratory evolution↗
DOE OSTI2026

pSN95

For recombinant expression of vanA (PP_3736 from Pseudomonas putida) with a C-terminal His tag

Adaptive laboratory evolution↗
DOE OSTI2026

RNAseq data for P. putida with vanillate

Illumina sequencing reads from RNA sequencing of vanillate-utilizing strains of Pseudomonas putida, described in Evolution and engineering of pathways for aromatic O-demethylation in Pseudomonas putida KT2440 by A. Bleem, et al. (2024)

Adaptive laboratory evolution↗
DOE OSTI2026

Evolution_and_engineering_of_pathways_for_aromatic_O-demethylation_in_Pseudomonas_putida_KT2440

Biological conversion of lignin from biomass offers a promising strategy for sustainable production of fuels and chemicals. However,aromatic compoundsderived from lignin commonly contain methoxy groups, andO-demethylation of these substrates is often a rate-limiting reaction that influences catabolic efficiency. Severalenzymefamilies catalyze aromaticO-demethylation, but they are rarely comparedin vivoto determine an optimal biocatalytic strategy. Here, two pathways for aromaticO-demethylation were compared inPseudomonas putidaKT2440. The native Rieske non-heme ironmonooxygenase(VanAB) and, separately, a heterologous tetrahydrofolate-dependentdemethylase(LigM) were constitutively expressed inP. putida, and the strains were optimized via adaptive laboratory evolution (ALE) withvanillateas a model substrate. All evolved strains displayed improved growth phenotypes, with the evolved strains harboring the native VanAB pathway exhibiting growth rates ∼1.8x faster than those harboring the heterologous LigM pathway.Enzyme kineticsandtranscriptomicsstudies investigated the contribution of selected mutations toward enhanced utilization of vanillate. The VanAB-overexpressing strains contained the most impactful mutations, including those in VanB, thereductasefor vanillateO-demethylase, PP_3494, a global regulator of vanillate catabolism, andfghA, involved in formaldehydedetoxification. These three mutations were combined into a single strain, which exhibited approximately 5x faster vanillate consumption than the wild-type strain in the first 8 h of cultivation. Overall, this study illuminates the details of vanillate catabolism in the context of two distinct enzymatic mechanisms,yielding a platform strain for efficientO-demethylation of lignin-related aromatic compounds to value-added products. This DOI contains supplementary material associated with the published manuscript.

CBI↗