title: Enzymatic production of urocanic acid by Achromobacter liquidum.
abstract: To develop an efficient method for the production of urocanic acid, optimal conditions for the production of microbial L-histidine ammonia lyase and for the conversion of L-histidine to urocanic acid by this enzyme were studied. A number of microorganisms were screened to test their ability to form and accumulate urocanic acid from L-histidine. Achromobacter liquidum was selected as the best organism. With this organism, enzyme activity as high as 2.0 units/ml could be produced by a shaking culture at 30 C in a medium containing glucose, urea, potassium phosphate, L-histidine, yeast extract, peptone, and inorganic salts. Appropriate addition of a surface-active agent to the reaction mixture shortened the time required for the conversion. A large amount of L-histidine was converted stoichiometrically to urocanic acid in 48 h at 40 C. Accumulated urocanic acid was readily isolated in pure form by ordinary procedures with isoelectric precipitation. Yields of isolated urocanic acid of over 92% from L-histidine were easily attainable. When the culture of Achromobacter liquidum was added to DL-histidine, D-histidine and urocanic acid were simultaneously obtained in high yields.
mesh_terms: D000179:Acrylates / Q000096:biosynthesis*; D000421:Alcaligenes / Q000201:enzymology / Q000378:metabolism*; D000642:Ammonia-Lyases / Q000378:metabolism*; D001419:Bacteria / Q000201:enzymology / Q000378:metabolism; D002854:Chromatography, Paper; D003470:Culture Media; D005285:Fermentation; D005470:Fluorometry; D005947:Glucose; D006639:Histidine / Q000378:metabolism; D006638:Histidine Ammonia-Lyase / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007093:Imidazoles / Q000096:biosynthesis*; D013045:Species Specificity; D013053:Spectrophotometry; D013473:Sunscreening Agents / Q000096:biosynthesis*; D013501:Surface-Active Agents; D013696:Temperature; D014508:Urea; D014559:Urocanate Hydratase / Q000378:metabolism
chemical_list: D000179:Acrylates; D003470:Culture Media; D007093:Imidazoles; D013473:Sunscreening Agents; D013501:Surface-Active Agents; D006639:Histidine; D014508:Urea; D014559:Urocanate Hydratase; D000642:Ammonia-Lyases; D006638:Histidine Ammonia-Lyase; D005947:Glucose