TY  - JOUR
AU  - Li, Wing-Jin
AU  - Narancic, Tanja
AU  - Kenny, Shane T.
AU  - Niehoff, Paul-Joachim
AU  - O’Connor, Kevin
AU  - Blank, Lars M.
AU  - Wierckx, Nick
TI  - Unraveling 1,4-Butanediol Metabolism in Pseudomonas putida KT2440
JO  - Frontiers in microbiology
VL  - 11
SN  - 1664-302X
CY  - Lausanne
PB  - Frontiers Media
M1  - FZJ-2020-01505
SP  - 382
PY  - 2020
N1  - Biotechnologie 1
AB  - Plastics, in all forms, are a ubiquitous cornerstone of modern civilization. Although humanity undoubtedly benefits from the versatility and durability of plastics, they also cause a tremendous burden for the environment. Bio-upcycling is a promising approach to reduce this burden, especially for polymers that are currently not amenable to mechanical recycling. Wildtype P. putida KT2440 is able to grow on 1,4-butanediol as sole carbon source, but only very slowly. Adaptive laboratory evolution (ALE) led to the isolation of several strains with significantly enhanced growth rate and yield. Genome re-sequencing and proteomic analysis were applied to characterize the genomic and metabolic basis of efficient 1,4-butanediol metabolism. Initially, 1,4-butanediol is oxidized to 4-hydroxybutyrate, in which the highly expressed dehydrogenase enzymes encoded within the PP_2674-2680 ped gene cluster play an essential role. The resulting 4-hydroxybutyrate can be metabolized through three possible pathways: (i) oxidation to succinate, (ii) CoA activation and subsequent oxidation to succinyl-CoA, and (iii) beta oxidation to glycolyl-CoA and acetyl-CoA. The evolved strains were both mutated in a transcriptional regulator (PP_2046) of an operon encoding both beta-oxidation related genes and an alcohol dehydrogenase. When either the regulator or the alcohol dehydrogenase is deleted, no 1,4-butanediol uptake or growth could be detected. Using a reverse engineering approach, PP_2046 was replaced by a synthetic promotor (14g) to overexpress the downstream operon (PP_2047-2051), thereby enhancing growth on 1,4-butanediol. This work provides a deeper understanding of microbial 1,4-butanediol metabolism in P. putida, which is also expandable to other aliphatic alpha-omega diols. It enables the more efficient metabolism of these diols, thereby enabling biotechnological valorization of plastic monomers in a bio-upcycling approach.
LB  - PUB:(DE-HGF)16
C6  - pmid:32256468
UR  - <Go to ISI:>//WOS:000525716600001
DO  - DOI:10.3389/fmicb.2020.00382
UR  - https://juser.fz-juelich.de/record/874551
ER  -