Isolation and partial characterization of bacteria in an anaerobic consortium that mineralizes 3-chlorobenzoic acid
A methanogenic consortium able to use 3-chlorobenzoic acid as its sole energy and carbon source was enriched from anaerobic sewage sludge. Seven bacteria were isolated from the consortium in mono- or coculture. They included: one dechlorinating bacterium, one benzoate-oxidizing bacterium, two butyrate-oxidizing bacteria, two H/sub 2/-consuming methanogens (methanospirillum hungatei PM-1 and Methanobacterium sp. strain PM-2), and a sulfate-reducing bacterium (Desulfovibrio sp.). The dechlorinating bacterium was a gram-negative, obligate anaerobe with a unique collar surrounding the cell. A medium containing rumen fluid supported minimal growth; pyruvate was the only substrate found to increase growth. The bacterium had a generation time of 4 to 5 days. 3-Chlorobenzoate was dechlorinated stoichiometrically to benzoate, which accumulated in the medium; the rate of dechlorination was ca. 0.1 pmol bacterium/sup -1/ day/sup -1/. The benzoate-oxidizing bacterium was a gram-negative, obligate anaerobe and could only be grown as a syntroph. Benzoate was the only substrate observed to support growth, and, when grown in coculture with M. hungatei, it was fermented to acetate and CH/sub 4/. One butyrate-oxidizing bacterium was a gram-negative, non-sporeforming, obligate anaerobe; the other was a gram-positive, sporeforming, obligate anaerobe. Both could only be grown as syntrophs. The substrates observed to support growth of both bacteria were butyrate, 2-DL-methylbutyrate, valerate, and caproate; isobutyrate supported growth of only the sporeforming bacterium. Fermentation products were acetate and CH/sub 4/ or acetate, propionate, and CH/sub 4/ when grown in coculture with M. hungatei. A mutualism among at least the dechlorinating, benzoate-oxidizing, and methane-forming members was apparently required for utilization of the 3-chlorobenzoate substrate. 21 references, 8 figures, 2 tables.
- Research Organization:
- Michigan State Univ., East Lansing
- OSTI ID:
- 5982884
- Journal Information:
- Appl. Environ. Microbiol.; (United States), Journal Name: Appl. Environ. Microbiol.; (United States) Vol. 48:4; ISSN AEMID
- Country of Publication:
- United States
- Language:
- English
Similar Records
Energetics and kinetics of anaerobic aromatic and fatty acid degradation. Progress report, March 1992--June 1995
Related Subjects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACETATES
ALKANES
AROMATICS
BACTERIA
BIOCONVERSION
BIODEGRADATION
BIOSYNTHESIS
CARBOXYLIC ACID SALTS
CHEMICAL REACTIONS
CHLORINATED AROMATIC HYDROCARBONS
DECOMPOSITION
DESULFOVIBRIO
FERMENTATION
HALOGENATED AROMATIC HYDROCARBONS
HYDROCARBONS
METABOLISM
METHANE
METHANOGENIC BACTERIA
MICROORGANISMS
MINERALIZATION
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
SEWAGE
SEWAGE SLUDGE
SLUDGES
SULFATE-REDUCING BACTERIA
SYNTHESIS
WASTES