EC Number   |
General Information |
Reference |
|---|
   1.1.1.B20 | malfunction |
extending the alpha6 helix of SmBdh to mimic the lower activity Enterobacter cloacae enzyme EcBdh results in reduction of SmBdh function to nearly 3% of the total activity. In great contrast, reduction of the corresponding alpha6 helix of the EcBdh to mimic the SmBdh structure results in about 70% increase in its activity |
-, 760761 |
| 1.1.1.B20 | malfunction |
the amount of meso-2,3-BD is highly reduced in a DELTAacoR mutant lacking the regulatory protein AcoR. The loss of locus pa4153, encoding (2R,3R)-2,3-BDH, has no effect on the ability of this strain to grow in (2S,3S)-2,3-BD but completely impairs its ability to utilize (2R,3R)-2,3-BD and meso-2,3-BD. The complementation of the pa4153 mutant strain with its gene successfully restores the growth ability. The DELTApa4153 PAO1 strain can grow in racemic acetoin, indicating that (2R,3R)-2,3-BDH contributes to 2,3-BD utilization by converting 2,3-BD into acetoin |
-, 756608 |
| 1.1.1.B20 | malfunction |
the budC knockout strain produces only the D-2,3-butanediol isomer with high yield and productivity. Deletion of budC gene causes a slight decrease (about 5-10%) in cell growth |
-, 742152 |
| 1.1.1.B20 | malfunction |
the growth of Bacillus licheniformis mutant strain MW3 (DELTAbudCDELTAgdh) is slightly lower than that of Bacillus licheniformis wild-type strain MW3, but the mutant strain can produce acetoin instead of 2,3-butanediol as its major product |
-, 761121 |
| 1.1.1.B20 | metabolism |
2,3-butanediol (2,3-BD) exists in three stereoisomeric forms: (2R,3R)-2,3-BD, meso-2,3-BD and (2S,3S)-2,3-BD. All three stereoisomers are transformed into acetoin by (2R,3R)-2,3-butanediol dehydrogenase (BDH) or (2S,3S)-2,3-BDH. Acetoin is cleaved to form acetyl-CoA and acetaldehyde by acetoin dehydrogenase enzyme system (AoDH ES). Genes encoding (2R,3R)-2,3-BDH, (2S,3S)-2,3-BDH and the E1 and E2 components of AoDH ES are identified as part of a 2,3-BD utilization operon. In addition, the regulatory protein AcoR promotes the expression of this operon using acetaldehyde, a cleavage product of acetoin, as its direct effector. Proposed model for 2,3-BD utilization in Pseudomonas aeruginosa strain PAO1 in downstream catabolic pathways, overview. Genes pa4148, pa4149, pa4150, pa4151, pa4152 and pa4153 comprise an operon responsible for 2,3-BD utilization, mutational analysis. Acetaldehyde is the direct inducer of the 2,3-BD utilization operon |
-, 756608 |
| 1.1.1.B20 | metabolism |
pathways for the synthesis of 2,3-butanediol in bacteria, overview |
741710 |
| 1.1.1.B20 | metabolism |
the proposed pathway from glucose to 2,3-butanediol in Paenibacillus brasilensis involves the enzyme, overview |
-, 760411 |
| 1.1.1.B20 | more |
identification of the the active tunnel of meso-2,3-BDH. The two short alpha-helices positioned away from the alpha4-helix possibly expose the hydrophobic ligand-binding cavity, gating the exit of product and cofactor from the activity pocket. AC binds in the active pocket including Ser139, Gln140, Ala141, Leu149, Tyr152, Gly183, Ile184, and Trp190. Residues Phe212 and Asn146 function as the key product-release sites. Three catalytic residues are Ser139, Tyr152, and Lys156. Docking study using the structure of meso-2,3-BDH (PDB ID 1GEG), molecular dynamics simulation |
761081 |
| 1.1.1.B20 | more |
Serratia marcescens is a very efficient producer of meso-2,3-butanediol (meso-2,3-BTD)from glucose |
-, 760759 |
| 1.1.1.B20 | more |
SmBdh shows a more extensive supporting hydrogen-bond network in comparison to the other well-studied Bdh enzymes, which enables improved substrate positioning and substrate specificity. The substrate-binding pocket is formed by two protein molecules, not a single peptide as found in all other reported Bdh enzymes. The C-terminus of molecule A protrudes into the groove between alpha7 helix and the alpha-turn alphat1 capping substrate-binding pocket of molecule Asymm and vice versa. The SmBdh active site is populated by a Gln247 residue contributed by the diagonally opposite subunit. The enzyme protein also contains a short alpha6 helix, which provides more efficient entry and exit of molecules from the active site, thereby contributing to enhanced substrate turnover. While coordinated active site formation is a unique structural characteristic of this tetrameric complex, the smaller alpha6 helix and extended hydrogen network contribute towards improved activity and substrate promiscuity of the enzyme. Gln247 plays a crucial role in SmBdh catalysis |
-, 760761 |
