Linked Life Data

1366365

Source:http://linkedlifedata.com/resource/pubmed/id/1366365

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-7-20
pubmed:abstractText
The Gibbs free energy changes in methanogenic granular biomass from sludge-bed reactors were evaluated using the in situ concentrations and partial pressures of metabolites during the metabolism of acetate, hydrogen, formate and propionate. Based on mass balance calculations it appeared that the degradation of propionate into acetate, hydrogen and bicarbonate was endergonic, even if propionate was effectively degraded. On the other hand, the methane-producing reactions, both from acetate and from hydrogen plus bicarbonate, were found to be exergonic and the free energy change was sufficient for the formation of ATP. Formate was detected in only one of the two reactors. When formate, instead of hydrogen, was considered as the electron carrier between propionate-degrading and methanogenic bacteria, similar thermodynamic results were obtained. The existence of trophic microniches in the granular biomass is suggested to explain propionate degradation even though the Gibbs free energy change in the liquid surrounding the granules was positive. Hence, to make propionate degradation exergonic the dissolved hydrogen concentration surrounding the propionate-degrading bacteria would have to be about 30 times lower than in the free liquid.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
B
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0175-7598
pubmed:author
pubmed:issnType
Print
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
88-92
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Thermodynamic evidence of trophic microniches in methanogenic granular sludge-bed reactors.
pubmed:affiliation
Biotechnology Research Institute, National Research Council Canada, Montréal, Québec.
pubmed:publicationType
Journal Article