Diversity and physiology of abundant Rhodoferax species in global wastewater treatment systems.

Wastewater treatment plants rely on complex microbial communities for bioconversion and removal of pollutants, but many process-critical species are still poorly investigated. One of these genera is Rhodoferax, an abundant core genus in wastewater treatment plants across the world. The genus has been associated with many metabolic traits such as iron reduction and oxidation and denitrification.

Quantification of Biologically and Chemically Bound Phosphorus in Activated Sludge from Full-Scale Plants with Biological P-Removal.

Phosphorus (P) is present in activated sludge from wastewater treatment plants in the form of metal salt precipitates, extracellular polymeric substances, or bound into the biomass, for example, as intracellular polyphosphate (poly-P). Several methods for a reliable quantification of the different P-fractions have recently been developed, and this study combines them to obtain a comprehensive P mass-balance of activated sludge from four enhanced biological phosphate removal (EBPR) plants. Chemical characterization by ICP-OES and sequential P fractionation showed that chemically bound P constituted 38-69% of total P, most likely in the form of Fe, Mg, or Al minerals.

Low Global Diversity of Microthrix, a Troublesome Filamentous Organism in Full-Scale WWTPs.

Microthrix is one of the most common bulking filamentous microorganisms found in activated sludge wastewater treatment plants (WWTPs) across the globe. One species, M. parvicella, is frequently observed, but global genus diversity, as well as important aspects of its ecology and physiology, are still unknown.

"Candidatus Dechloromonas phosphoritropha" and "Ca. D. phosphorivorans", novel polyphosphate accumulating organisms abundant in wastewater treatment systems.

Members of the genus Dechloromonas are often abundant in enhanced biological phosphorus removal (EBPR) systems and are recognized putative polyphosphate accumulating organisms (PAOs), but their role in phosphate removal is still unclear. Here, we used 16S rRNA gene sequencing and fluorescence in situ hybridization (FISH) to investigate the abundance and distribution of Dechloromonas spp. in Danish and global wastewater treatment plants.

" Galacturonibacter soehngenii" Shows Acetogenic Catabolism of Galacturonic Acid but Lacks a Canonical Carbon Monoxide Dehydrogenase/Acetyl-CoA Synthase Complex.

Acetogens have the ability to fixate carbon during fermentation by employing the Wood-Ljungdahl pathway (WLP), which is highly conserved across Bacteria and Archaea. In a previous study, product stoichometries in galacturonate-limited, anaerobic enrichment cultures of " Galacturonibacter soehngenii," from a novel genus within the , suggested the simultaneous operation of a modified Entner-Doudoroff pathway for galacturonate fermentation and a WLP for acetogenesis. However, a draft metagenome-assembled genome (MAG) based on short reads did not reveal homologs of genes encoding a canonical WLP carbon-monoxide-dehydrogenase/acetyl-Coenzyme A synthase (CODH/ACS) complex.