Transformation of indole by methanogenic and sulfate-reducing microorganisms isolated from digested sludge

Journal Article · Mon Jan 01 04:00:00 EST 1990 · Microbial Ecology; (United States)

DOI:https://doi.org/10.1007/BF02543875· OSTI ID:7013418

Shanker, R; Bollag, J M ^[1]

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1. Pennsylvania State Univ., University Park (United States)

In the present study, mineralization of an aromatic N-heterocyclic molecule, indole, by microorganisms present in anaerobically digested sewage sludge was examined. The first step in indole mineralization was the formation of a hydroxylated intermediate, oxindole. The rate of transformation of indole to oxindole and its subsequent disappearance was dependent on the concentration of inoculum and indole and the incubation temperature. Methanogenesis appeared to be the dominant process in the mineralization of indole in 10% digested sludge even in the presence of high concentrations of sulfate. Enrichment of the digested sludge with sulfate as an electron acceptor allowed the isolation of a metabolically stable mixed culture of anaerobic bacteria which transformed indole to oxindole and acetate, and ultimately to methane and carbon dioxide. This mixed culture exhibited a predominance of sulfate-reducers over methanogens with more than 75% of the substrate mineralized to carbon dioxide. The investigation demonstrates that indole can be transformed by both methanogenic and sulfate-reducing microbial populations.

• DOE Contract Number: FG02-87ER60556
• OSTI ID: 7013418
• Journal Information: Microbial Ecology; (United States), Journal Name: Microbial Ecology; (United States) Vol. 20; ISSN MCBEB; ISSN 0095-3628
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANAEROBIC DIGESTION
AROMATICS
AZAARENES
AZOLES
BACTERIA
BIOCONVERSION
BIODEGRADATION
BIOLOGICAL MATERIALS
BIOLOGICAL VARIABILITY
BIOLOGICAL WASTES
CHEMICAL REACTIONS
CLEANING
DECOMPOSITION
DECONTAMINATION
DIGESTION
GENETIC VARIABILITY
GROWTH
HETEROCYCLIC COMPOUNDS
INDOLES
MANAGEMENT
MATERIALS
METHANOGENIC BACTERIA
MICROORGANISMS
MINERALIZATION
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXYGEN COMPOUNDS
PROCESSING
PYRROLES
SEWAGE
SEWAGE SLUDGE
SLUDGES
SULFATE-REDUCING BACTERIA
SULFATES
SULFUR COMPOUNDS
WASTE MANAGEMENT
WASTE PROCESSING
WASTES