Probes designed and optimized in this study.

§ Coverage of groups as defined in MiDAS database (Release 1.20)[3]. Values given as group hits/ group totals. Percentage values are given in parenthesis; ⌘ For optimization with ‘Full-scale sludge’ samples taken from the Odense North East, Odense North West, Ejby Mølle and Randers BNR WWTPs were used. In each case optimization with the different plants gave similar dissociation profiles (data not shown); # Requirement of accessory probes: If available, isolates with single-base mismatches to the probe were used to assess the requirement for a competitor probe. Competitor probes perfectly match the target site in the listed isolate. If the mismatch alone is enough to prevent non-target binding of the labeled probe, at the recommended formamide concentration, then the competitor probe is assessed as not being required (note: it is recommended that competitor probes are included for un-validated mismatches); helper probes assessed on ability to improve fluorescence signal of the associated labeled probe. NA = Not applicable; ND = Not determined; Φ Determined optimal formamide concentration for use in FISH hybridizations. Probes designed and optimized in this study.