Affiliation:
1. Division of Environmental and Nutritional Sciences, School of Public Health. University of California, Los Angeles, California 90024
Abstract
A thermophilic strain of
Methanosarcina,
designated
Methanosarcina
strain TM-1, was isolated from a laboratory-scale 55°C anaerobic sludge digestor by the Hungate roll-tube technique. Penicillin and
d
-cycloserine, inhibitors of peptidoglycan synthesis, were used as selective agents to eliminate contaminating non-methanogens.
Methanosarcina
strain TM-1 had a temperature optimum for methanogenesis near 50°C and grew at 55°C but not at 60°C. Substrates used for methanogenesis and growth by
Methanosarcina
strain TM-1 were acetate (12-h doubling time), methanol (7- to 10-h doubling time), methanol-acetate mixtures (5-h doubling time), methylamine, and trimethylamine. When radioactively labeled acetate was the sole methanogenic substrate added to the growth medium, it was predominantly split to methane and carbon dioxide. When methanol was also present in the medium, the metabolism of acetate shifted to its oxidation and incorporation into cell material. Electrons derived from acetate oxidation apparently were used to reduce methanol. H
2
-CO
2
was not used for growth and methanogenesis by
Methanosarcina
strain TM-1. When presented with both H
2
-CO
2
and methanol,
Methanosarcina
strain TM-1 was capable of limited hydrogen metabolism during growth on methanol, but hydrogen metabolism ceased once the methanol was depleted.
Methanosarcina
strain TM-1 required a growth factor (or growth factors) present in the supernatant of anaerobic digestor sludge. Growth factor requirements and the inability to use H
2
-CO
2
are characteristics not found in other described
Methanosarcina
strains. The high numbers of
Methanosarcina
-like clumps in sludges from thermophilic digestors and the fast generation times reported here for
Methanosarcina
TM-1 indicate that
Methanosarcina
may play an important role in thermophilic methanogenesis.
Publisher
American Society for Microbiology
Subject
Ecology,Applied Microbiology and Biotechnology,Food Science,Biotechnology
Reference35 articles.
1. New approach to the cultivation of methanogenic bacteria: 1-mercaptoethanesulfonic acid (HS-CoM)-dependent growth of Methanobacterium ruminantium in a pressurized atmosphere;Balch W. E.;Appl. Environ. Microbiol.,1976
2. Methanogenesis from acetate: enrichment studies;Baresi L.;Appl. Environ. Microbiol.,1978
3. Studies upon the methane-producing bacteria;Barker H. A.;Arch. Microbiol.,1936
4. Barker H. A. 1956. Bacterial fermentations p. 1-27. John Wiley & Sons New York.
5. Bryant M. P. 1965. Rumen methanogenic bacteria p. 411-418. In R. W. Dougherty (ed.) Physiology and digestion in the ruminant. Butterworth Inc. Washington D.C.
Cited by
246 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献