Purification and Characterization of a Novel (S)-Enantioselective Transaminase fromPseudomonas fluorescensKNK08-18 for the Synthesis of Optically Active Amines

Abstract

Pseudomonas fluorescens KNK08-18, showing (S)-selective transaminase activity, was isolated from soil by an enrichment culture method using (S)-7-methoxy-2-aminotetraline as the main nitrogen source. A transaminase was purified from the strain to homogeneity in seven steps. The relative mass of the enzyme was estimated to be 53 kDa on SDS-polyacrylamide gel electrophoresis and 120 kDa by gel filtration, suggesting a homodimeric structure. The optimal pH and temperature for enzyme activity were about 8.0-8.5 and 40 °C. The purified enzyme produced (S)-7-methoxy-2-aminotetraline, (S)-SMA, from 7-methoxy-2-tetralone (SMT) with high enantioselectivity. Although (S)-1-phenylethylamine was the best amino donor, β-alanine and 4-aminobutyric acid, which are good substrates for typical ω-amino acid transaminase (EC 2.6.1.18) and GABA transaminase (2.6.1.19), were not reacted. It aminated a broad range of carbonyl compounds containing aromatic, non-aromatic, and acidic and non-acidic substrates.

Transaminase biocatalysis: optimization and application

“…KNK168 TA was until recently the only R-selective TA to be identified from experimental microorganism screening. Moreover, a number of microorganisms with substrate specificities corresponding to those of the screening culture including Bacillus megaterium SC6394, 38 Moraxella lacunata WZ34, 39 Pseudomonas fluorescens KNK08-18, 40 Alcaligenes denitrificans Y2k-2, 41 Mesorhizobium sp. LUK 42 and Pseudomonas sp.…”

Concise Chemoenzymatic Three‐Step Total Synthesis of Isosolenopsin through Medium Engineering

“…Pseudomonas fluorescens ,13a,13b and Hyphomonas neptunium ,9f the influence of the concentration of water-miscible (DMF, DME, DMSO) and immiscible (toluene) solvents at concentrations in the range 5–40 vol.-% was investigated [for the analytical scale: 25 m m 3a (6 mg/mL); 1.00 mL total volume]. The first two enzymes are ( S )-selective, whereas the latter two are ( R )-selective.…”

Control of the Helical Chirality of Enantiopure Sulfinyl (Z)‐Azobenzene‐Based Photoswitches

“…Focussing on the four most promising ω‐TAs identified, originating from Arthrobacter citreus ,13c Arthrobacter sp 13d . Pseudomonas fluorescens ,13a,13b and Hyphomonas neptunium ,9f the influence of the concentration of water‐miscible (DMF, DME, DMSO) and immiscible (toluene) solvents at concentrations in the range 5–40 vol.‐% was investigated [for the analytical scale: 25 m M 3a (6 mg/mL); 1.00 mL total volume]. The first two enzymes are ( S )‐selective, whereas the latter two are ( R )‐selective.…”