Metabolism of dibenzo-p-dioxin by Sphingomonas sp. strain RW1

Journal Article · Sun Mar 01 00:00:00 EST 1992 · Applied and Environmental Microbiology; (United States)

OSTI ID:7206270

Wittich, R M; Wilkes, H; Sinnwell, V; Francke, W; Fortnagel, P ^[1]

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1. Univ. Hamburg (Germany)

In the course of screening for dibenzo-p-dioxin-utilizing bacteria, a Sphingomonas sp. strain was isolated from enrichment cultures inoculated with water samples from the river Elbe. The isolate grew with both the biaryl ethers dibenzo-p-dioxin and dibenzofuran (DF) as the sole sources of carbon and energy, showing doubling times of about 8 and 5 h, respectively. Biodegradation of the two aromatic compounds initially proceeded after an oxygenolytic attack at the angular position adjacent to the ether bridge, producing 2,2{prime},3-trihydroxydiphenyl ether or 2,2{prime},3-trihydroxybiphenyl from the initially formed dihydrodiols, which represent extremely unstable hemiacetals. Results obtained from determinations of enzyme activities and oxygen consumption suggest meta cleavage of the trihydroxy compounds. During dibenzofuran degradation, hydrolysis of 2-hydroxy-6-oxo-6-(2-hydroxyphenyl)-hexa-2,4-dienoate yielded salicylate, which was branched into the catechol meta cleavage pathway and the gentisate pathway. Catechol obtained from the product of meta ring fission of 2,2{prime},3-trihydroxydiphenyl ether was both ortho and meta cleaved by Sphingomonas sp. strain RW1 when this organism was grown with dibenzo-p-dioxin.

• OSTI ID: 7206270
• Journal Information: Applied and Environmental Microbiology; (United States), Vol. 58:3; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
DIOXIN
BIODEGRADATION
BACTERIA
BENZOFURANS
BIOLOGICAL PATHWAYS
ENZYME ACTIVITY
METABOLISM
RIVERS
WATER POLLUTION
CHEMICAL REACTIONS
DECOMPOSITION
FURANS
HETEROCYCLIC COMPOUNDS
MICROORGANISMS
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
POLLUTION
STREAMS
SURFACE WATERS
560300* - Chemicals Metabolism & Toxicology