Isolation and characterization of highly (R)-specific N-acetyl-1-phenylethylamine amidohydrolase, a new enzyme from Arthrobacter aurescens AcR5b.
A new amidohydrolase deacetylating several N-acetyl-1-phenylethylamine derivatives (R)-specifically was found in Arthrobacter aurescens AcR5b. The strain was isolated from a wet haystack by enrichment culture with (R)-N-acetyl-1-phenylethylamine as the sole carbon source. (R) and (S)-N-acetyl-1-phenylethylamine do not serve as inducers for acylase formation. By improving the growth conditions the enzyme production was increased 47-fold. The amidohydrolase was purified to homogeneity leading to a 5.2-fold increase of the specific activity with a recovery of 67%. A molecular mass of 220 kDa was estimated by gel filtration. Sodium dodecyl sulfate/polyacrylamide gel electrophorosis shows two subunits with molecular masses of 16 kDa and 89 kDa. The optimum pH and temperature were pH 8 and 50 degrees C, respectively. The enzyme was stable in the range of pH 7-9 and at temperatures up to 30 degrees C. The enzyme activity was inhibited by Cu2+, Co2+, Ni2+, and Zn2+, and this inhibition was reversed by EDTA.M.
Graf
M
M
Pharmaceuticals Divisions, Novartis International Inc., Basel, Switzerland.
Brunella
A
A
Kittelmann
M
M
Laumen
K
K
Ghisalba
O
O
D000581:Amidohydrolases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D001173:Arthrobacter / Q000201:enzymology*; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D013379:Substrate Specificity; D013696:Temperature
D000581:Amidohydrolases