Periodic Reporting for period 4 - BIOSUSAMIN (The design and development of efficient biocatalytic cascades and biosynthetic pathways for the sustainable production of amines)
Berichtszeitraum: 2018-09-01 bis 2020-10-31
One of the major limitations was the relatively narrow substrate scope of the known amine dehydrogenases. Thus, the BioSusAmin team has studied the properties of the available amine dehydrogenases and their substrate scope for the reductive amination of a panel of structurally diverse prochiral ketones was elucidated. This initial work was published in Green Chemistry (IF 9.125; DOI: 10.1039/C6GC01987K). Later, the BioSusAmin project generated a tool-box of amine dehydrogenase that complements the enzymes previously available. The team applied the so called rational-guide enzyme evolution or semi-rational enzyme engineering. For example, the wild-type ε-lysine 6-dehydrogenase from Geobacillus s (Lys-EDH) was chosen as scaffold for the engineering of S-selective and R-selective AmDHs with expanded substrate scope. Our work delivered new AmDH that are active towards bulky-bulky and industrially relevant prochiral ketones. This work was published in Nat. Commun. DOI: 10.1038/s41467-019-11509-x and a world patent was granted. We also generate a second and further generation libraries of AmDHs to obtain new variants possessing dual ADH-AmDH activity. This led to the first example of “alcohol aminase” enzymes. These variants were applied in the one-enzyme hydrogen-borrowing amination of alcohols and the work was published in Chem. Eur J. DOI: 10.1002/chem.202003140. Finally, during our studies on amine dehydrogenases (AmDHs) for the synthesis of secondary and tertiary amines, we gained new insights into the catalytic mechanism of these enzymes (work published in ChemBioChem, 2019, 20, 800).
- The develop of the first hydrogen-borrowing bioamination of alcohols (and other related methodologies) for the one-pot and concurrent enzymatic amination of alcohols.
- The introduction of these unnatural pathways into living system for performing the asymmetric bioamination of alcohols in vivo.
- A methodology for the redox-neutral conversion of inexpensive and available feedstock into polyamide monomers. The approach is flexible as it can be implemented in vitro using isolated enzymes as well as in vivo using engineered E. coli strains that harbour the genes for the required engineered enzymes.
- We have shown that alcohol dehydrogenase activity can be created from an amine dehydrogenase activity and vice versa. This novel approach will open up many new possibilities for engineering of amine dehydrogenases starting from structurally diverse alcohol dehydrogenases.