Production of cis-1,2-dihydrocatechols of high synthetic value by whole-cell fermentation using Escherichia coli JM109 (pDTG601): A detailed study

Site‐Directed Mutagenesis Studies on the Toluene Dioxygenase Enzymatic System: Role of Phenylalanine 366, Threonine 365 and Isoleucine 324 in the Chemo‐, Regio‐, and Stereoselectivity

“…Interestingly, changes in chemoselectivity were observed with both substrates (7) and (8). Hydroxylation of the benzylic position for propylbenzene (7) was not detected for both cases, indicating that a change in substrate accommodation in the active site probably precludes this position from 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 being oxidised. We have recently reported a computational model for TDO that nicely explained and predicted the outcome of the biotransformation for mono and 1,4-disubstituted arenes.…”

“…[7] Fresh plates of E. coli JM109 (pDTG601) and E. coli JM109 (pTDO M ) were streaked from frozen stocks, and a single colony was used to inoculate 5 mL of LB-Amp which was incubated in orbital shaker overnight (150 rpm, 37 8C). Two 500 mL Erlenmeyer flasks containing 150 mL of MSB medium were inoculated with 1.5 mL of the grown culture, and grown for 12 h in orbital shaker at 37 8C, 150 rpm.…”

“…[1a] A recent publication by our group describes the biotechnological procedure to obtain 35 g/L of cis-3-bromocyclo-3,5-hexadiene-1,2-diol using the recombinant E. coli JM109 (pDTG601). [7] The TDO enzymatic system admits a high structural diversity of substrates, and the dioxygenation reaction is highly regio-and stereoselective. [1a] Regarding monosubstituted benzene derivatives, dioxygenation always takes place at C2-C3 in a stereodefined manner to afford diols of type (1) (except for fluorobenzene, where trace amounts of the regioisomeric diol at C3-C4 are also obtained) (Scheme 1B).…”

Toluene Dioxygenase‐Catalysed Oxidation of Benzyl Azide to Benzonitrile: Mechanistic Insights for an Unprecedented Enzymatic Transformation

“…We next studied product formation profiles in ab iotransformation carried out in a5Lb ioreactor ( Figure 1C). [13] The plots showa ni nitial lag phase for the formation of cyanodiol 3,a nd then both curves (which representt he formation of products 1 + 2 and formation of cyanodiol 3)d isplayc omparable initial slopes.T hese profilesa re consistentw ith the proposed initialf ormation of benzonitrile from benzyla zide and subsequentd ioxygenation to 3.…”

New, Homochiral Synthons Obtained through Simple Manipulations of Enzymatically Derived 3-Halo-cis-1,2-dihydrocatechols

“…[1] Hence, for example, using Escherichia coli JM109 (pDTG601), bromobenzene and chlorobenzene are both bio-transformed, under whole-cell conditions, into the metabolites 1a and 1b, respectively. [1,2] These types of conversions proceed in essentially quantitative yield, deliver the cis-1,2-dihydrocatechols in .99.8 % ee, and can be carried out on the kilogram if not the tonne scale. Furthermore, compounds such as 1a and 1b have proven to be extraordinarily versatile starting materials in chemical synthesis as evidenced by their conversion into a wide range of natural products including carbohydrates, terpenoids, and alkaloids.…”