Reevaluation of the Phylogenetic Diversity and Global Distribution of the Genus "Candidatus Accumulibacter"

Francesca Petriglieri, Caitlin M Singleton, Zivile Kondrotaite, Morten K D Dueholm, Elizabeth A McDaniel, Katherine D McMahon, Per H Nielsen*

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

19 Citations (Scopus)
109 Downloads (Pure)

Abstract

“Candidatus Accumulibacter” was the first microorganism identified as a polyphosphate-accumulating organism (PAO) important for phosphorus removal from wastewater. Members of this genus are diverse, and the current phylogeny and taxonomic framework appear complicated, with most publicly available genomes classified as “Candidatus Accumulibacter phosphatis,” despite notable phylogenetic divergence. The ppk1 marker gene allows for a finer-scale differentiation into different “types” and “clades”; nevertheless, taxonomic assignments remain inconsistent across studies. Therefore, a comprehensive reevaluation is needed to establish a common understanding of this genus, in terms of both naming and basic conserved physiological traits. Here, we provide this reassessment using a comparison of genome, ppk1, and 16S rRNA gene-based approaches from comprehensive data sets. We identified 15 novel species, along with “Candidatus Accumulibacter phosphatis,” “Candidatus Accumulibacter delftensis,” and “Candidatus Accumulibacter aalborgensis.” To compare the species in situ, we designed new species-specific fluorescence in situ hybridization (FISH) probes and revealed their morphology and arrangement in activated sludge. Based on the MiDAS global survey, “Ca. Accumulibacter” species were widespread in wastewater treatment plants (WWTPs) with phosphorus removal, indicating process design as a major driver for their abundance. Genome mining for PAO-related pathways and FISH-Raman microspectroscopy confirmed the potential for PAO metabolism in all “Ca. Accumulibacter” species, with detection in situ of the typical PAO storage polymers. Genome annotation further revealed differences in the nitrate/nitrite reduction pathways. This provides insights into the niche differentiation of these lineages, potentially explaining their coexistence in the same ecosystem while contributing to overall phosphorus and nitrogen removal.

Original languageEnglish
Article numbere0001622
JournalmSystems
Volume7
Issue number3
ISSN2379-5077
DOIs
Publication statusPublished - 28 Jun 2022

Keywords

  • diversity
  • metagenome-assembled genome
  • phylogeny
  • ppk1 gene
  • “Candidatus Accumulibacter”

Fingerprint

Dive into the research topics of 'Reevaluation of the Phylogenetic Diversity and Global Distribution of the Genus "Candidatus Accumulibacter"'. Together they form a unique fingerprint.

Cite this