Detection and characterisation of catechol 2,3-dioxygenase in an indigenous soil <Emphasis Type="Italic">Pseudomonad</Emphasis> by MALDI-TOF MS using a column separation

The key enzyme catalyzing the second step in the phenol degradation meta-cleavage pathway (C23O) has been purified to homogeneity from a new bacterial strain, which belongs to genus Pseudomonas. The species was growing on phenol as carbon source. The C23O was detected and identified by absorption spectroscopy. The protein was isolated using sucrose density centrifugation and anion exchange chromatography. The purified protein showed a molecular mass of 32 kDa to sodium dodecyl sulfate polyacrylamid gel electrophoresis and an isoelectric point of 5 estimated by analytical isoelectrical focusing. Matrix-assisted laser desorption ionization-time of flight mass spectrometry and peptide mapping was attempted for the identification of the isolated protein and proteins involved in the metabolic pathway.