MICROBIAL-METABOLISM OF QUINOLINE AND RELATED-COMPOUNDS .14. PURIFICATION AND PROPERTIES OF 1H-3-HYDROXY-4-OXOQUINOLINE OXYGENASE, A NEW EXTRADIOL CLEAVAGE ENZYME FROM PSEUDOMONAS-PUTIDA STRAIN-33/1

1H-3-Hydroxy-4-oxoquinoline oxygenase was purified to apparent homogeneity from Pseudomonas putida strain 33/1 which can use IH-4-oxoquinoline as sole source of carbon. The molecular mass of the enzyme was determined to 26000 Da by gel chromatography and by SDS polyacrylamide gel electrophoresis.The enzyme is labile at temperatures above 30-degrees-C and has a pH optimum of 8.0. It requires oxygen for the reaction and is significantly inhibited by metal ions like Cu2+, Zn 2+, Hg2+ and by 4-chloromercuribenzoate. The enzyme is specific only for 1-H--3-Hydroxy-4-oxoquinoline; the apparent K(m) value for this substrate is 24-mu-m.