Protein Variants | Comment | Organism |
---|---|---|
additional information | Paenibacillus polymyxa is used for the production of R-,R-2,3-butanediol in exceptionally high enantiomeric purity. Rational metabolic engineering efforts to increase productivity and product titers have been restricted due to limited genetic accessibility of the organism. By use of CRISPR-Cas9 mediated genome editing, six metabolic mutant variants are generated and compared in batch fermentations. Downstream processing is facilitated by completely eliminating exopolysaccharide formation through the combined knockout of the sacB gene and the clu1 region, encoding for the underlying enzymatic machinery of levan and paenan synthesis. Knockout constructs are generated to eliminate undesirable side-products of 2,3-BDL fermentations. Spore formation is inhibited by deletion of spoIIE, thereby disrupting the sporulation cascade of Paenibacillus polymyxa. Optimization of the carbon flux towards 2,3-butanediol is achieved by deletion of the lactate dehydrogenase ldh1 and decoupling of the butanediol dehydrogenase from its natural regulation via constitutive episomal expression. The improved strain shows 45% increased productivity, reaching a final concentration of 43.8 g/l butanediol. A yield of 0.43 g/g glucose is achieved, accounting for 86% of the theoretical maximum. Paenibacillus polymyxa is transformed by conjugation using Escherichia coli strain S17-1 harboring the various plasmids. Method optimization and evaluation, overview | Paenibacillus polymyxa |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
(R)-acetoin + NADH + H+ | Paenibacillus polymyxa | high level production of (R,R)-butane-2,3-diol | (R,R)-butane-2,3-diol + NAD+ | - |
r | |
(R)-acetoin + NADH + H+ | Paenibacillus polymyxa DSM 365 | high level production of (R,R)-butane-2,3-diol | (R,R)-butane-2,3-diol + NAD+ | - |
r |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Paenibacillus polymyxa | - |
- |
- |
Paenibacillus polymyxa DSM 365 | - |
- |
- |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
(R)-acetoin + NADH + H+ | - |
Paenibacillus polymyxa | (R,R)-butane-2,3-diol + NAD+ | - |
r | |
(R)-acetoin + NADH + H+ | high level production of (R,R)-butane-2,3-diol | Paenibacillus polymyxa | (R,R)-butane-2,3-diol + NAD+ | - |
r | |
(R)-acetoin + NADH + H+ | - |
Paenibacillus polymyxa DSM 365 | (R,R)-butane-2,3-diol + NAD+ | - |
r | |
(R)-acetoin + NADH + H+ | high level production of (R,R)-butane-2,3-diol | Paenibacillus polymyxa DSM 365 | (R,R)-butane-2,3-diol + NAD+ | - |
r |
Synonyms | Comment | Organism |
---|---|---|
BDH | - |
Paenibacillus polymyxa |
butanediol dehydrogenase | - |
Paenibacillus polymyxa |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
in vivo assay at | Paenibacillus polymyxa |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
6 | - |
in vivo assay at | Paenibacillus polymyxa |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
NAD+ | - |
Paenibacillus polymyxa | |
NADH | - |
Paenibacillus polymyxa |
General Information | Comment | Organism |
---|---|---|
metabolism | overview of 2,3-BDL biosynthesis pathway and byproducts in microaerobic conditions of Paenibacillus polymyxa strain DSM 365 starting from sucrose as a substrate | Paenibacillus polymyxa |