Anaerobic metabolism of aromatic compounds by phototrophic bacteria: Progress report

Technical Report · Fri Dec 19 04:00:00 EST 1986

OSTI ID:6912406

Harwood, C S; Gibson, J

Vast quantities of aromatic compounds in the form of lignin, lignin derivatives, and aromatic pollutants are continually being introduced into the biosphere and much of this material accumulates in anaerobic environments. This project seeks to elucidate anaerobic routes of benzoate and 4-hydroxybenzoate metabolism by the photorophic bacterium, Rhodopseudomonas palustris. Recent evidence suggests that diverse aromatics must first be metabolized to form one or the other of these compounds prior to cleavage of the aromatic ring and so these pathways probably play general role as major degradative routes. R. palustris is particularly well suited for these studies because its ability to separate carbon metabolism from energy generating mechanisms frees it from the thermodynamic constraints that restrict the anaerobic metabolism of aromatics by pure cultures of fermentative bacteria. Studies include identification of the number and specificity of enzymes involved in benzoate and 4-hydroxybenzoate metabolism, identification of cofactors and electron carriers involved in each pathway, and a determination of the precise nature of the products formed. Mutants that are blocked in aromatic metabolism have been isolated. These mutants will be used, together with physiological approaches, to identify compounds (inducers and repressors) that regulate the expression of genes for aromatic degradation. 8 refs., 2 figs., 1 tab.

• Research Organization: Cornell Univ., Ithaca, NY (USA)
• DOE Contract Number: FG02-86ER13495
• OSTI ID: 6912406
• Report Number(s): DOE/ER/13495-T1; ON: DE87003570
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
140504* -- Solar Energy Conversion-- Biomass Production & Conversion-- (-1989)
550200 -- Biochemistry
550500 -- Metabolism
59 BASIC BIOLOGICAL SCIENCES
ANAEROBIC DIGESTION
AROMATICS
BACTERIA
BENZOIC ACID
BIOCHEMICAL REACTION KINETICS
BIOCONVERSION
BIODEGRADATION
CARBOHYDRATES
CARBOXYLIC ACIDS
CATABOLISM
CHEMICAL REACTIONS
CHROMATOGRAPHY
DECOMPOSITION
DIGESTION
ENZYMES
FRACTIONATION
HYDROXY COMPOUNDS
KINETICS
LIGASES
LIGNIN
LIQUID COLUMN CHROMATOGRAPHY
MANAGEMENT
METABOLISM
MICROORGANISMS
MONOCARBOXYLIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PHENOLS
POLYSACCHARIDES
PROCESSING
REACTION KINETICS
RHODOPSEUDOMONAS
SACCHARIDES
SEPARATION PROCESSES
STRUCTURE-ACTIVITY RELATIONSHIPS
WASTE MANAGEMENT
WASTE PROCESSING