Total DNA was isolated from swine feces and a swine waste storage pit and used as templates for PCR amplification of archaeal 16 rDNA using specific primers. Only the sample from the center of the waste pit produced a PCR product. DNA sequence analyses of random clones demonstrated a variety of methanogenic archaea. Six groups of sequences were identified, including those similar to Methanobrev...

PeiW (UniProtKB Q7LYX0) and PeiP (UniProtKB Q77WJ4) are the two major pseudomurein endoisopeptidases (Pei) that are known to cleave pseudomurein cell-wall sacculi of the members of the methanogenic orders Methanobacteriales and Methanopyrales. Both enzymes, originating from prophages specific for some methanogenic archaeal species, hydrolyze the ϵ(Ala)-Lys bond of the peptide linker between adj...

To precisely control the application of methyl fluoride (CH3F) for analysis of methanogenic pathways, the influence of 0-10% CH3F on bacterial and archaeal communities in a thermophilic methanogenic sludge was investigated. The results suggested that CH3F acts specifically on acetoclastic methanogenesis. The inhibitory effect stabilized at an initial concentration of 3-5%, with around 90% of th...

Zoige wetland in Tibetan plateau represents a cold environment at high altitude where significant methane emission has been observed. However, it remains unknown how the production and emission of CH4 from Zoige wetland will respond to a warming climate. Here we investigated the temperature sensitivity of methanogen community in a Zoige wetland soil under the laboratory incubation conditions. O...

When microorganisms eluted from upper Hudson River sediment were cultured without any substrate except polychlorobiphenyl (PCB)-free Hudson River sediment, methane formation was the terminal step of the anaerobic food chain. In sediments containing Aroclor 1242, addition of eubacterium-inhibiting antibiotics, which should have directly inhibited fermentative bacteria and thereby should have ind...

Marine surface sediments, which are replete with sulfate, are typically considered to be devoid of endogenous methanogenesis. Yet, methanogenic archaea are present in those sediments, suggesting a potential for methanogenesis. We used an isotope dilution method based on sediment bag incubation and spiking with 13C-CH4 to quantify CH4 turnover rates in sediment from Aarhus Bay, Denmark. In two i...

Methanogenic archaea possess unusual seryl-tRNA synthetases (SerRS), evolutionarily distinct from the SerRSs found in other archaea, eucaryotes and bacteria. Our recent X-ray structural analysis of Methanosarcina barkeri SerRS revealed an idiosyncratic N-terminal domain and catalytic zinc ion in the active site. To shed further light on substrate discrimination by methanogenic-type SerRS, we se...

Biological methanogenesis is linked to permanent water logged systems, e.g., rice field soils or lake sediments. In these systems the methanogenic community as well as the pathway of methane formation are well-described. By contrast, the methanogenic potential of river sediments is so far not well-investigated. Therefore, we analyzed (a) the methanogenic potential (incubation experiments), (b) ...