Enrichment and dynamics of novel syntrophs in a methanogenic hexadecane-degrading culture from a Chinese oilfield.
Methanogenic communities that degrade alkanes have been reported. However, little is known about the key players involved in the process. Methanogenic hexadecane-degrading consortia were enriched from an oilfield (Shengli, China). The microbial dynamics during the transfer incubations were monitored using terminal restriction fragment length polymorphism (T-RFLP) fingerprinting of 16S rRNA genes in combination with cloning and sequencing. The archaeal community shifted from a predominance of aceticlastic Methanosaeta during early cultivation to a substantial increase in hydrogenotrophic Methanoculleus in the highly enriched culture. Bacterial T-RFs 161 and 164 bp were consistently detected during the incubation and became dominant in the highly enriched culture. T-RF 161 bp primarily represented uncultured Waste Water of Evry 1 bacterium, which was possibly associated with Candidatus Cloacamonas acidaminovorans (99.7% sequence similarity). T-RF 164 bp could be assigned to both Thermotogaceae, with the closest relative being Candidatus Mesotoga sulfurreducens (similarity of 97%) and Syntrophaceae, with Smithella propionica as the closest relative (similarity of 96-97%). These bacterial lineages were potentially capable of syntrophic interactions with methanogen partners during hexadecane degradation. Partial assA genes (encoding the α-subunit of alkylsuccinate synthase) were also detected, implying that the mechanism of fumarate addition may function in the hexadecane activation.
College of Resources and Environmental Sciences, China Agricultural University, Beijing, China.
Lei
L
Cheng
Junpeng
J
Rui
Qiang
Q
Li
Hui
H
Zhang
Yahai
Y
Lu
D000473:Alkanes / Q000378:metabolism*; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D002681:China; D019641:DNA, Archaeal / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D019605:Euryarchaeota / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D008697:Methane / Q000378:metabolism; D059013:Microbial Consortia; D061329:Oil and Gas Fields / Q000382:microbiology*; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D012336:RNA, Ribosomal, 16S / Q000235:genetics
D000473:Alkanes; D019641:DNA, Archaeal; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; C007932:n-hexadecane; D008697:Methane