Abstract Global change is modifying meteorological and hydrological factors that influence the thermal regime of water bodies. These modifications can lead to longer stratification periods with enlarged hypolimnetic anoxic periods, which promote heterotrophic anaerobic processes alter reservoir carbon cycling. Here, we quantified aerobic (aerobic respiration, denitrification, iron manganese red...

Molar tooth structures are ptygmatically folded and microspar-filled structures common in early- and mid-Proterozoic (∼2,500-750 million years ago, Ma) subtidal successions, but extremely rare in rocks <750 Ma. Here, on the basis of Mg and S isotopes, we show that molar tooth structures may have formed within sediments where microbial sulphate reduction and methanogenesis converged. The converg...

Methanogenesis from the non-physiological C1 donors thioproline, thiazolidine, hexamethylenetetramine, formaldehyde (HCHO), and HOCH2-S-coenzyme M (CoM) was catalyzed by cell extracts of Methanobacterium thermoautotrophicum under a hydrogen atmosphere. Tetrahydromethanopterin (H4MPT) and HS-CoM were required in the reaction mixture. The non-physiological compounds were found to be in chemical e...

The work investigated why anaerobic digesters treating food waste and operating at high ammonia concentrations suffer from propionic acid accumulation which may result in process failure. The results showed deficiency of selenium, essential for both propionate oxidation and syntrophic hydrogenotrophic methanogenesis, leads to this while supplementation allows operation at substantially higher o...

The global budget of atmospheric CH4 , which is on the order of 500-600 Tg CH4 per year, is mainly the result of environmental microbial processes, such as archaeal methanogenesis in wetlands, rice fields, ruminant and termite digestive systems and of microbial methane oxidation under anoxic and oxic conditions. This review highlights recent progress in the research of anaerobic CH4 oxidation, ...

A spontaneous mutant of Methanothermobacter thermautotrophicus resistant to the Na+/H+ antiporter inhibitor amiloride was isolated. The Na+/H+ exchanger activity in the mutant cells was remarkably decreased in comparison with wild-type cells. Methanogenesis rates in the mutant strain were higher than wild-type cells and resistant to the inhibitory effect of 2 mM amiloride. In contrast, methanog...

The anaerobic digestion of filter cake and its co-digestion with bagasse, and the effect of gradual increase of the organic loading rate (OLR) from start-up to overload were investigated. Understanding the influence of environmental and technical parameters on the development of particular methanogenic pathway in the biogas process was an important aim for the prediction and prevention of proce...

Microbial methane consumption in anoxic sediments significantly impacts the global environment by reducing the flux of greenhouse gases from ocean to atmosphere. Despite its significance, the biological mechanisms controlling anaerobic methane oxidation are not well characterized. One current model suggests that relatives of methane-producing Archaea developed the capacity to reverse methanogen...

In natural environments methane is usually produced by aceticlastic and hydrogenotrophic methanogenic archaea. However, some methanogens can use C(1) compounds such as methanol as the substrate. To determine the contributions of individual substrates to methane production, the stable-isotope values of the substrates and the released methane are often used. Additional information can be obtained...

four in vitro experiments (exp.) were conducted to evaluate lavender essential oil (leo) effects at 0 (control), 250 (low dose), 500 (medium dose), 750 and 1000 µl per l(high doses) of incubation medium on rumen gas production kinetics (exp.1), ruminal digestibility and fermentation (exp.2), methane production (exp.3) and rumen acidosis (exp.4). the asymptote of gas production (a) increased qua...