Group-specific Quantification of mcrA genes of Methanogenic Archaea and "Candidatus Methanoperedens" by Digital PCR.

Digital PCR is a technique that quantifies target genes based on the absence or presence of the targets in PCR amplicons. The present study exami-ned group-specific probes for the quantification of mcrA genes in six methanogenic archaeal groups and "Candidatus Methanoperedens" by digital PCR with the universal primers ML-f and ML-r. A digital PCR ana-lysis of paddy field soil detected all the targets, with the dominant and minor groups being Methanomicrobiales and Methanobrevibacter spp., respectively (10 and 10 copies [g dry soil]). This method has the potential to reveal the dynamics of specific methanogenic archaeal groups in the environment.