Purification and characterization of a catechol 1,2-dioxygenase from a phenol degrading Candida albicans TL3.
A eukaryotic catechol 1,2-dioxygenase (1,2-CTD) was produced from a Candida albicans TL3 that possesses high tolerance for phenol and strong phenol degrading activity. The 1,2-CTD was purified via ammonium sulfate precipitation, Sephadex G-75 gel filtration, and HiTrap Q Sepharose column chromatography. The enzyme was purified to homogeneity and found to be a homodimer with a subunit molecular weight of 32,000. Each subunit contained one iron. The optimal temperature and pH were 25 degrees C and 8.0, respectively. Substrate analysis showed that the purified enzyme was a type I catechol 1,2-dioxygenase. This is the first time that a 1,2-CTD from a eukaryote (Candida albicans) has been characterized. Peptide sequencing on fragments of 1,2-CTD by Edman degradation and MALDI-TOF/TOF mass analyses provided information of amino acid sequences for BLAST analysis, the outcome of the BLAST revealed that this eukaryotic 1,2-CTD has high identity with a hypothetical protein, CaO19_12036, from Candida albicans SC5314. We conclude that the hypothetical protein is 1,2-CTD.
Tsai
San-Chin
SC
Department of Applied Chemistry, National Chiao Tung University, 1001 Ta-Hseh Rd., Hsinchu, Taiwan.
Li
Yaw-Kuen
YK
D001673:Biodegradation, Environmental; D002176:Candida albicans / Q000201:enzymology* / Q000378:metabolism*; D050548:Catechol 1,2-Dioxygenase / Q000302:isolation & purification* / Q000378:metabolism; D019800:Phenol / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D019800:Phenol; D050548:Catechol 1,2-Dioxygenase