Diversity of the resident microbiota in a thermophilic municipal biogas plant

Abstract

Biogas plants continuously convert biological wastes mainly into a mixture of methane, CO2 and H2O-a conversion that is carried out by a consortium of bacteria and archaea. Especially in the municipal plants dedicated towards waste treatment, the reactor feed may vary considerably, exposing the resident microbiota to a changing variety of substrates. To evaluate how and if such changes influence the microbiology, an established biogas plant (6,600 m3, up to 600 m3 biogas per h) was followed over the course of more than 2 years via polymerase chain reaction-denaturing gradient gel electrophoresis of 16S rRNA genes and subsequent sequencing. Both the bacterial and the archaeal community remained stable over the investigation. Of the bacterial consortium, about half of the sequences were in decreasing order of occurrence: Thermoacetogenium sp., Anaerobaculum mobile, Clostridium ultunense, Petrotoga sp., Lactobacillus hammesii, Butyrivibrio sp., Syntrophococcus sucromutans, Olsenella sp., Tepidanaerobacter sp., Sporanaerobacter acetigenes, Pseudoramibacter alactolyticus, Lactobacillus fuchuensis or Lactobacillus sakei, Lactobacillus parabrevis or Lactobacillus spicheri and Enterococcus faecalis. The other half matched closely to ones from similar habitats (thermophilic anaerobic methanogenic digestion). The archaea consisted of Methanobrevibacter sp., Methanoculleus bourgensis, Methanosphaera stadtmanae, Methanimicrococcus blatticola and uncultured Methanomicrobiales. The role of these species in methane production is discussed.

Rapid establishment of thermophilic anaerobic microbial community during the one-step startup of thermophilic anaerobic digestion from a mesophilic digester

“…(5 0 -TTACCGCGGCTGCTGGCAC-3 0 ) (Delong, 1992;Koike et al, 2007) for bacteria and Arch344F (5 0 -ACGGGGYGCAG- (Weiss et al, 2008) for archaea.…”

Olsenella umbonata sp. nov., a microaerotolerant anaerobic lactic acid bacterium from the sheep rumen and pig jejunum, and emended descriptions of Olsenella, Olsenella uli and Olsenella profusa

“…Olsenellae are found in the healthy (Ozutsumi et al, 2005;Cho et al, 2006;Hernandez et al, 2008) and acidotic (Tajima et al, 2000) bovine rumen. Moleculargenetic studies have also reported the detection of Olsenella-related clones in the gastrointestinal tracts of humans (Martinez-Medina et al, 2006;Khachatryan et al, 2008;Krogius-Kurikka et al, 2009), pigs (Leser et al, 2002;Tsukahara & Ushida, 2002;Dowd et al, 2008), wallabies (Chhour et al, 2008) and chickens (Lu et al, 2003) and in diverse anaerobic environmental sites (Bowman et al, 2006;Wongtanet et al, 2007;Weiss et al, 2008;Rivière et al, 2009). This indicates that the habitats of the olsenellae generally comprise the oral cavity and gastrointestinal tract of homoeothermic vertebrates and that non-animal habitats also exist.…”

Addition of a palm oil analogue to oil-reservoir formation water stimulates the growth of Anaerobaculum sp. and a novel taxon from the Deferribacteraceae

“…OTU ecb9 was classifi ed under the genus Anaerobaculum (Table 1) by the RDP classifi er. Anaerobaculum species have previously been identifi ed as taxa that produce hydrogen anaerobically from a range of substrates along with oxidized carbon, typically in the form of acetate (Maune and Tanner, 2011;Menes and Muxi, 2002;Weiss et al, 2008) and presumably a similar form of oxidized carbon is being produced on the addition of POA2.…”