title: Activity of a carboxyl-terminal truncated form of catechol 2,3-dioxygenase from Planococcus sp. S5.
abstract: Catechol 2,3-dioxygenases (C23Os, E.C.1.13.12.2) are two domain enzymes that catalyze degradation of monoaromatic hydrocarbons. The catalytically active C-domain of all known C23Os comprises ferrous ion ligands as well as residues forming active site pocket. The aim of this work was to examine and discuss the effect of nonsense mutation at position 289 on the activity of catechol 2,3-dioxygenase from Planococcus strain. Although the mutant C23O showed the same optimal temperature for activity as the wild-type protein (35 °C), it exhibited activity slightly more tolerant to alkaline pH. Mutant enzyme exhibited also higher affinity to catechol as a substrate. Its K(m) (66.17 µM) was approximately 30% lower than that of wild-type enzyme. Interestingly, removal of the C-terminal residues resulted in 1.5- to 1.8-fold (P < 0.05) increase in the activity of C23OB61 against 4-methylcatechol and 4-chlorocatechol, respectively, while towards catechol the activity of the protein dropped to about 80% of that of the wild-type enzyme. The results obtained may facilitate the engineering of the C23O for application in the bioremediation of polluted areas.
authors.affiliation: Department of Biochemistry, Faculty of Biology and Environment Protection, University of Silesia in Katowice, Jagiellonska 28, 40-032 Katowice, Poland.
authors.forename: Katarzyna
authors.identifier: 0000-0003-2821-568X
authors.initials: K
authors.lastname: Hupert-Kocurek
authors.affiliation: Department of Biochemistry, Faculty of Biology and Environment Protection, University of Silesia in Katowice, Jagiellonska 28, 40-032 Katowice, Poland.
authors.forename: Danuta
authors.identifier: 0000-0002-6681-0992
authors.initials: D
authors.lastname: Wojcieszyńska
authors.affiliation: Department of Biochemistry, Faculty of Biology and Environment Protection, University of Silesia in Katowice, Jagiellonska 28, 40-032 Katowice, Poland.
authors.forename: Urszula
authors.identifier: 0000-0001-6349-3808
authors.initials: U
authors.lastname: Guzik
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D050557:Catechol 2,3-Dioxygenase / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism; D004789:Enzyme Activation; D004795:Enzyme Stability; D006841:Hydrocarbons, Aromatic / Q000737:chemistry*; D058642:Planococcus Bacteria / Q000145:classification / Q000201:enzymology*; D013045:Species Specificity; D013329:Structure-Activity Relationship; D013379:Substrate Specificity
chemical_list: D006841:Hydrocarbons, Aromatic; D002245:Carbon Dioxide; C041069:carboxyl radical; D050557:Catechol 2,3-Dioxygenase