In:
Applied and Environmental Microbiology, American Society for Microbiology, Vol. 70, No. 7 ( 2004-07), p. 4048-4052
Abstract:
Acetate conversion pathways of methanogenic consortia in acetate-fed chemostats at dilution rates of 0.025 and 0.6 day −1 were investigated by using 13 C-labeled acetates, followed by gas chromatography-mass spectrometry (GC-MS) analysis of the CH 4 and CO 2 produced. Nonaceticlastic syntrophic oxidation by acetate-oxidizing syntrophs and hydrogenotrophic methanogens was suggested to occupy a primary pathway (approximately 62 to 90%) in total methanogenesis at the low dilution rate. In contrast, aceticlastic cleavage of acetate by aceticlastic methanogens was suggested to occupy a primary pathway (approximately 95 to 99%) in total methanogenesis at the high dilution rate. Phylogenetic analyses of transcripts of the methyl coenzyme M reductase gene ( mcrA ) confirmed that a significant number of transcripts of the genera Methanoculleus (hydrogenotrophic methanogens) and Methanosarcina (aceticlastic methanogens) were present in the chemostats at the low and high dilution rates, respectively. The mcrA transcripts of the genus Methanosaeta (aceticlastic methanogens), which dominated the population in a previous study (T. Shigematsu, Y. Tang, H. Kawaguchi, K. Ninomiya, J. Kijima, T. Kobayashi, S. Morimura, and K. Kida, J. Biosci. Bioeng. 96: 547-558, 2003), were poorly detected at both dilution rates due to the limited coverage of the primers used. These results demonstrated that the dilution rate could cause a shift in the primary pathway of acetate conversion to methane in acetate-fed chemostats.
Type of Medium:
Online Resource
ISSN:
0099-2240
,
1098-5336
DOI:
10.1128/AEM.70.7.4048-4052.2004
Language:
English
Publisher:
American Society for Microbiology
Publication Date:
2004
detail.hit.zdb_id:
223011-2
detail.hit.zdb_id:
1478346-0
SSG:
12
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