Chemical structure and biodegradability of halogenated aromatic compounds. Substituent effects on 1,2-dioxygenation of catechol.

摘要: 1. The influence of halogen substituents on the 1,2-dioxygenation catechols was investigated. results obtained with two isoenzymes pyrocatechase I and II from haloarene-utilizing Pseudomonas sp. B 13 benzoate-induced cells Alcaligenes eutrophus B.9 were compared. 2. Substituents catechol found to interfere O2 binding by 13, whereas Km value for kept constant at different concentrations. 3. Electron-attracting decreased values catechols. 4. Results studies substituted demonstrated narrow stereospecificities pseudomonas alcaligenes B.9. In contrast, a low steric hindrance in observed. 5. Low pK′1 resulted Michaelis constants. 6. such as reaction rates 1,2-dioxygenation. correlation Vmax. observed substituent sigma+ (Okamoto–Brown equation) distinctly greater than Hammett9s sigma values. corresponding logVmax. against considerably disturbed influences substituents.