title: Degradation of 3,4-dichloro- and 3,4-difluoroaniline by Pseudomonas fluorescens 26-K.
abstract: 3,4-Dichloro- and 3,4-difluoroanilines were degraded by Pseudomonas fluorescens 26-K under aerobic conditions. In the presence of glucose strain degraded 170 mg/L of 3,4-dichloroaniline (3,4-DCA) during 2-3 days. Increasing of toxicant concentration up to 250 mg/L led to degradation of 3,4-DCA during 4 days and its intermediates during 5-7 days. Without cosubstrate and nitrogen source degradation of 3,4-DCA took place too, but more slowly--about 40% of toxicant at initial concentration 75 mg/L was degraded during 15 days. 3,4-Difluoroaniline (3,4-DFA) (initial concentration 170 mg/L) was degraded by Pseudomonas fluorescens 26-K during 5-7 days. The strain was able to completely degrade up to 90 mg/L of 3,4-DFA, without addition of cosubstrate and nitrogen during 15 days. Degradation of fluorinated aniline was accompanied by intensive defluorination. Activity of catechol 2,3-dioxygenase (C2,3DO) (0.230 micromol/min/mg of protein) was found in the culture liquid of the strain, grown with 3,4-DCA and glucose. This fact, as well as, the presence of 3-chloro-4-hydroxyaniline as a metabolite suggested that 3,4-DCA degradation pathway includes dehalogenation and hydroxylation of aromatic ring followed by its subsequent cleaving by C2,3DO. On the contrary, activity of catechol 1,2-dioxygenase (C1,2DO) (0.08 micromol/min/mg of protein) was found in the cell-free extract of biomass grown on 3,4-DFA. 3-Fluoro-4-hydroxyaniline as intermediate was found in this cell-free extract.
authors.affiliation: G. K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Pushchino, Moscow region, Russia.
authors.forename: Vassili M
authors.initials: VM
authors.lastname: Travkin
authors.forename: Inna P
authors.initials: IP
authors.lastname: Solyanikova
authors.forename: Ivonne M C M
authors.initials: IM
authors.lastname: Rietjens
authors.forename: Jacques
authors.initials: J
authors.lastname: Vervoort
authors.forename: Willem J H
authors.initials: WJ
authors.lastname: van Berkel
authors.forename: Ludmila A
authors.initials: LA
authors.lastname: Golovleva
mesh_terms: D000814:Aniline Compounds / Q000032:analysis / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002851:Chromatography, High Pressure Liquid; D004305:Dose-Response Relationship, Drug; D009584:Nitrogen / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D010105:Oxygenases / Q000378:metabolism; D011551:Pseudomonas fluorescens / Q000201:enzymology / Q000378:metabolism*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism*; D013379:Substrate Specificity; D013997:Time Factors
chemical_list: C475303:3,4-difluoroaniline; D000814:Aniline Compounds; D012989:Soil Pollutants; C014464:3,4-dichloroaniline; D010105:Oxygenases; D009584:Nitrogen; D010100:Oxygen