Anaerobic aryl reductive dehalogenation of halobenzoates by cell extracts of Desulfomonile tiedjei

Journal Article · Mon Oct 01 00:00:00 EDT 1990 · Applied and Environmental Microbiology; (United States)

OSTI ID:5462690

DeWeerd, K A; Suflita, J M ^[1]

---

1. Univ. of Oklahoma, Norman (USA)

The authors studied the transformation of halogenated benzoates by cell extracts of a dehalogenating anaerobe, Desulfomonile tiedjei. The authors found that cell extracts possessed aryl reductive dehalogenation activity. The activity was heat labile and dependent on the addition of reduced methyl viologen, but not on that of reduced NAD, NADP, flavin mononucleotide, flavin adenine dinucleotide, desulfoviridin, cytochrome c{sub 3}, or benzyl viologen. Dehalogenation activity in extracts was stimulated by formate, CO, or H{sub 2}, but not by pyruvate plus coenzyme A or by dithionite. The pH and temperature optima for aryl dehalogenation were 8.2 and 35{degree}C, respectively. The rate of dehalogenation was proportional to the amount of protein in the assay mixture. The substrate specificity of aryl dehalogenation activity for various aromatic compounds in D. tiedjei cell extracts was identical to that of whole cells, except differences were observed in the relative rates of halobenzoate transformation. Dehalogenation was 10-fold greater in D. tiedjei extracts prepared from cells cultured in the presence of 3-chlorobenzoate, suggesting that the activity was inducible. Aryl reductive dehalogenation in extracts was inhibited by sulfite, sulfide, and thiosulfate, but not sulfate. Experiments with combinations of substrates suggested that cell extracts dehalogenated 3-iodobenzoate more readily than either 3,5-dichlorobenzoate or 3-chlorobenzoate. Dehalogenation activity was found to be membrane associated. This is the first report characterizing aryl dehalogenation activity in cell extracts of an obligate anaerobe.

• OSTI ID: 5462690
• Journal Information: Applied and Environmental Microbiology; (United States), Vol. 56:10; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
BACTERIA
METABOLISM
HALOGENATED AROMATIC HYDROCARBONS
BIODEGRADATION
ANAEROBIC CONDITIONS
BENZOIC ACID
CARBON MONOXIDE
CELL MEMBRANES
DEHALOGENATION
FORMATES
HYDROGEN
INHIBITION
STIMULATION
SULFUR COMPOUNDS
AROMATICS
CARBON COMPOUNDS
CARBON OXIDES
CARBOXYLIC ACID SALTS
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
ELEMENTS
MEMBRANES
MICROORGANISMS
MONOCARBOXYLIC ACIDS
NONMETALS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
550500* - Metabolism