Identification of acrylate, the product of the dehydration of (R)-lactate catalysed by cell-free extracts from Clostridium propionicum.
Cell extracts from Clostridium propionicum harvested in the late log-phase catalysed the dehydration of (R)-lactate to acrylate at a maximum rate of 0.06 U/mg protein. The unsaturated acid was identified by high-performance liquid chromatography and as p-bromophenacyl ester by gas chromatography combined with mass spectroscopy. The amount of acrylate formed was dependent on protein and (R)-lactate concentrations. However, due to product inhibition the yield of acrylate did not exceed 0.5%. Like the dehydration of (R)-2-hydroxyglutarate to glutaconate the dehydration of (R)-lactate to acrylate was inhibited by 1 mM hydroxylamine, 1mM azide, 0.1 mM dinitrophenol, 10 mM EDTA or by exposure to air. A radical mechanism is postulated.
D000179:Acrylates / Q000378:metabolism*; D002384:Catalysis; D055598:Chemical Phenomena; D002621:Chemistry; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D003013:Clostridium / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D006836:Hydro-Lyases / Q000037:antagonists & inhibitors / Q000378:metabolism; D007773:Lactates / Q000378:metabolism*; D013058:Mass Spectrometry
D000179:Acrylates; D007773:Lactates; D006836:Hydro-Lyases; C045581:lactate dehydratase