Problems in detecting methanogens in anaerobic reactors by 16S rRNA gene amplicon sequencing: which method is more reliable?

CALLEJAS, CECILIA; ETCHEBEHERE, CLAUDIA; ERIJMAN, LEONARDO; WENZEL, JORGE; CABEZAS, ANGELA; BOVIO, PATRICIA; GUERRERO, LEANDRO

Hiroshima

Congreso; 8th IWA Microbial Ecology and Water Engineering Specialist Conference; 2019

International Water Association (IWA)

The bacterial community from methanogenic reactors has been successfully studied by 16S rRNA gene amplicon sequencing in the past years. But, methanogens are still in general poorly covered by the Universal primers. In order to circumvent this limitation, two sets of primers specifically design to detect Archaea were tested in samples taken from a full scale UASB methanogenic reactor. The results were compared with results obtained using the Universal primers and using a metagenomic approach without primer bias. Our results show that when using the Universal primers only 1.76% of Archaea were detected while the metagenome analysis detected 11.36% of Archaea. Using the two primer sets specific for Archaea, similar results were obtained. Two groups of methanogens were detected, with a high dominance of Methanosaeta. This genus was not detected with the Universal primers although abundant according to the metagenomic approach