Discovering Anammox Bacteria in Anthropogenic Environments.

Bacteria capable of anaerobic ammonia oxidation (anammox) have been shown to play an important role in global nitrogen cycling in marine environment, but terrestrial occurrences of these microbes have been given little attention.  This study examined the presence of anammox bacteria in the anthropogenic environments of constructed wetlands, riparian buffers, pastures, human septic systems, and swine lagoons.  Several Planctomycetales- and anammox-specific 16S rRNA primer sets were tested and two nested PCR protocols were developed for phylogenetic analysis of anammox bacteria.  Using these protocols, we detected anammox bacterial DNA in all anthropogenic environments examined.  Phylogenetic analysis of cloned 16S rRNA PCR fragments indicated that composition of anammox bacteria varied with environments, with Candidatus "Jettenia asiatica" being found only in swine lagoon.