Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.3389/fmicb.2016.02034
Titel (primär) Trace elements induce predominance among methanogenic activity in anaerobic digestion
Autor Wintsche, B.; Glaser, K.; Sträuber, H.; Centler, F.; Liebetrau, J.; Harms, H.; Kleinsteuber, S. ORCID logo
Quelle Frontiers in Microbiology
Erscheinungsjahr 2016
Department UMB; iDiv
Band/Volume 7
Seite von art. 2034
Sprache englisch
Keywords biogasreactor; methanogenesis; mcrA; Methanosarcina; Methanoculleus; ampliconsequencing; T-RFLP
UFZ Querschnittsthemen RU4;
Abstract Trace elements (TE) play an essential role in all organisms due to their functions in enzyme complexes. In anaerobic digesters, control, and supplementation of TEs lead to stable and more efficient methane production processes while TE deficits cause process imbalances. However, the underlying metabolic mechanisms and the adaptation of the affected microbial communities to such deficits are not yet fully understood. Here, we investigated the microbial community dynamics and resulting process changes induced by TE deprivation. Two identical lab-scale continuous stirred tank reactors fed with distiller’s grains and supplemented with TEs (cobalt, molybdenum, nickel, tungsten) and a commercial iron additive were operated in parallel. After 72 weeks of identical operation, the feeding regime of one reactor was changed by omitting TE supplements and reducing the amount of iron additive. Both reactors were operated for further 21 weeks. Various process parameters (biogas production and composition, total solids and volatile solids, TE concentration, volatile fatty acids, total ammonium nitrogen, total organic acids/alkalinity ratio, and pH) and the composition and activity of the microbial communities were monitored over the total experimental time. While the methane yield remained stable, the concentrations of hydrogen sulfide, total ammonia nitrogen, and acetate increased in the TE-depleted reactor compared to the well-supplied control reactor. Methanosarcina and Methanoculleus dominated the methanogenic communities in both reactors. However, the activity ratio of these two genera was shown to depend on TE supplementation explainable by different TE requirements of their energy conservation systems. Methanosarcina dominated the well-supplied anaerobic digester, pointing to acetoclastic methanogenesis as the dominant methanogenic pathway. Under TE deprivation, Methanoculleus and thus hydrogenotrophic methanogenesis was favored although Methanosarcina was not overgrown by Methanoculleus. Multivariate statistics revealed that the decline of nickel, cobalt, molybdenum, tungsten, and manganese most strongly influenced the balance of mcrA transcripts from both genera. Hydrogenotrophic methanogens seem to be favored under nickel- and cobalt-deficient conditions as their metabolism requires less nickel-dependent enzymes and corrinoid cofactors than the acetoclastic and methylotrophic pathways. Thus, TE supply is critical to sustain the activity of the versatile high-performance methanogen Methanosarcina.
dauerhafte UFZ-Verlinkung
Wintsche, B., Glaser, K., Sträuber, H., Centler, F., Liebetrau, J., Harms, H., Kleinsteuber, S. (2016):
Trace elements induce predominance among methanogenic activity in anaerobic digestion
Front. Microbiol. 7 , art. 2034 10.3389/fmicb.2016.02034