Supplementary web Figure 1. 16S rRNA-based phylogenetic trees showing the affiliation of all cultured and uncultured members of the nine “” lineages. The consensus tree is based on maximum-likelihood analysis (AxML) of full- length sequences (>1,300 nucleotides) performed with a 50% conservation filter for the “”. Named type species are indicated by boldface type. Bar indicates 10% estimated sequence divergence. Polytomic nodes connect branches for which a relative order could not be determined unambiguously by applying neighbor- joining, maximum-parsimony, and maximum-likelihood treeing methods. Numbers at branches indicate parsimony bootstrap values in percent. Branches without numbers had bootstrap values of less than 75%. The minimum 16S rRNA sequence similarity for each “Rhodocyclales” lineage is shown.

P+ sludge clone SBR1021, AF204250 P+ sludge clone GC152, AF204242 Kraftisried wwtp clone KRA42, AY689087 Kraftisried wwtp clone S28, AF072922 Kraftisried wwtp clone A13, AF072927 Kraftisried wwtp clone H23, AF072926 Kraftisried wwtp clone S40, AF234757 lineage 100 Kraftisried wwtp clone H12, AF072923 100 Kraftisried wwtp clone H20, AF072920 92.5% 89 rape root clone RRA12, AY687926 100 P+ sludge clone SBR1001, AF204252 P- sludge clone SBR2080, AF204251 P+ sludge clone GC24, AF204243 mine water clone I12, AY187895 100 93 denitrifying cholesterol-degrading bacterium 72Chol, Y09967 Sterolibacterium denitrificans, AJ306683

Kraftisried wwtp clone KRZ64, AY689092 Kraftisried wwtp clone KRZ70, AY689093 Kraftisried wwtp clone H10, AF234693 Kraftisried wwtp clone H13, AF234737 Kraftisried wwtp clone H40, AF234704 Kraftisried wwtp clone H11, AF234708 Kraftisried wwtp clone H22, AF234697 Kraftisried wwtp clone H27, AF234722 Kraftisried wwtp clone S21, AF234738 Kraftisried wwtp clone A16, AF234726 98 EBPR reactor clone PHOS-HC20, AF314418 drinking water biofilm isolate B5, AF035051 resiniphila, AJ505852 Zoogloea lineage , AJ505853 94.3% 74 Zoogloea resiniphila, AJ505854 100 Zoogloea resiniphila, AJ505851 Zoogloea resiniphila, AJ011506 TCB-transforming microbial consortium clone SJA-21, AJ009455

74 EBPR reactor clone HP1 A03, AF502233 EBPR-SBR clone, AF527582 , X74913 activated sludge clone bnp269 98 Zoogloea ramigera, D14254 76 98 Zoogloea ramigera, D14257 Kraftisried wwtp clone KRZ65, AY689091 Kraftisried wwtp clone H7, AF234684

Azovibrio restrictus, AF011346 99 restrictus, AF011348 Azovibrio lineage 100 Azovibrio restrictus, L15532 97.5% Azovibrio sp., AF011349

10% TCE-contaminated site clone, AY133068 TCE-contaminated site clone, AY133073 sp. HA, AF482683 Azoarcus sp. CIB, AF515816 Azoarcus sp. M3, Y11040 , L33688 Azoarcus sp. T, AF129465 Azoarcus tolulyticus, L33693 Azoarcus tolulyticus, L33690 Azoarcus sp. ToN1 , X83534 Azoarcus toluvorans, L33692 Azoarcus sp., U44853 , X77679 Azoarcus sp. CC-11, AB033745 Azoarcus toluvorans, L33689 Azoarcus sp. 22LIN, Y13222 Azoarcus tolulyticus, AF229857 Azoarcus tolulyticus, AF229876 Azoarcus tolulyticus, L33694 Azoarcus tolulyticus, L33691 Azoarcus tolulyticus, L33687 Azoarcus tolulyticus, AF229861 Azoarcus tolulyticus strain BL11, AF123075 Azoarcus toluclasticus, AF123076 Azoarcus toluclasticus, AF123077 Azoarcus sp. FL05 , AF011330 100 Betaproteobacterium pCyN1, Y17284 Azoarcus sp. EbN1, X83531 "Azoarcus buckelii", AJ315676 , Y14701 Azoarcus sp. PbN1, X83532 Azoarcus sp. HxN1, AF331975

100 acetate-enrichment clone, AF395431 Azoarcus sp. CR23, AF011328 Azoarcus sp. PH002, AF011329 Azoarcus sp. T3, Y11041 Kraftisried wwtp clone S23, AF072921 Kraftisried wwtp clone A33, AF072925 Azoarcus- 75 Kraftisried wwtp clone S3, AF072918 - Kraftisried wwtp clone H35, AF234732 Denitromonas lineage Kraftisried wwtp clone H25, AF072919 100 Kraftisried wwtp clone S10, AF234762 91.6% Kraftisried wwtp clone H30, AF072924 ikaite tufa column clone, AJ431352

95 Thauera sp. PIV-1, AJ505850 TCB-transforming microbial consortium clone SJA-186, AJ009507 P+ sludge clone SBR1011, AF204253 Thauera sp. DNT-1, AB066262 Thauera sp. mz1t, AF110005 "Thauera phenylacetica", AJ315678 "Thauera aminoaromatica", AJ315677 100 soil clone AX39, X64373 , X68491 Thauera selenatis, Y17591 P+ sludge clone SBR1022, AF204254 75 , AJ315679 Thauera aromatica, AJ315680 Azoarcus sp. mXyN1, X83533 Thauera sp. T1, U95176 Thauera aromatica, AJ315681 Thauera aromatica, X77118 Thauera aromatica, AF229881 Thauera aromatica, AF229882 Thauera aromatica, AF229887 Thauera aromatica, AF229868 Thauera aromatica, AF229867 Thauera chlorobenzoica, AF123264 Thauera mechernichensis, Y17590 98 " butanovora", AB021377 , AJ005816 betaproteobacterial clone, AY098637

100 Betaproteobacterium pCyN2, Y17285 , AJ005818 Thauera terpenica, AJ005817 , AF011345 Azoarcus sp. BH72, AF011344 95 Azoarcus communis, AF011343 Azoarcus sp. LU1, AJ007007 hot spring microbial mat isolate OS-ac-16, U46748 Denitromonas aromaticus, AB049763

10% EBPR reactor clone HP1 A13, AF502224 EBPR reactor clone HP1 B54, AF502232 EBPR reactor clone HP1 B23, AF502225 P+++ sludge clone SBRA220, AF204244 P+++ sludge clone SBRA245A, AF204245 activated sludge clone UCT N173, AY064179 100 EBPR activated sludge clone SA34, AF245349 97 EBPR reactor clone Ebpr16, AF255631 EBPR reactor clone Ebpr15, AF255641 activated sludge clone UCT N161, AY064178 EBPR reactor clone PHOS-HC05, AF314417 activated sludge clone UCT N112, AY064176 Candidatus "Accumulibacter phosphatis", AJ224937 EBPR reactor clone HP1 A50, AF502226 - EBPR reactor clone HP1 B75, AF502227 - EBPR reactor clone HP1 A21, AF502228 Accumulibacter lineage EBPR reactor clone HP1 A49, AF502229 EBPR reactor clone HP1 A26, AF502231 92.1% 75 EBPR reactor clone HP1 A31, AF502230 91 P+++ sludge clone SBRB34, AF204247 80 activated sludge clone UCT N032, AY062125 P++ sludge clone SBRP112, AF204248 100 termite gut clone, AB062831 termite gut clone Rs-K54, AB089103 Propionivibrio pelophilus, AF016690 Propionivibrio dicarboxylicus, Y17601 , AJ307983 benzene-contaminated groundwater clone ZZ15C5, AY214205 100 , D16208 90 Rhodocyclus tenuis, D16210 , M34132 Rhodocyclus tenuis, D16209

groundwater clone S15A-MN2, AJ534664 groundwater clone S15A-MN93, AJ534665 groundwater clone S15A-MN28, AJ534661 oryzae, AF011347 Azospira sp., AF011351 TCE-contaminated site clone, AY133096 Azospira (Dechlorosoma) sp. PDX, AF323490 TCB-transforming microbial consortium clone SJA-52, AJ009466 Azospira lineage groundwater clone S15A-MN6, AJ534663 groundwater clone S15A-MN34, AJ534659 95.1% Azospira (Dechlorosoma) sp. PCC, AY126453 Azospira (Dechlorosoma) sp. Iso1, AF170350 Azospira (Dechlorosoma) sp. Iso2, AF170351 Azospira sp. (Dechlorosoma suillum), AF170348 100 Azospira (Dechlorosoma) sp. SDGM, AF170349 89 Azospira (Dechlorosoma) sp. KJ, AF323491 100 beta proteobacterium TW2, AF503539 Azospira (Dechlorosoma) sp. AH, AY171616

TCE-contaminated site clone ccs2105, AY133067 TCE-contaminated site clone, AY133076 TCE-contaminated site clone, AY133087 TCE-contaminated site clone, AY133075 TCE-contaminated site clone AC1, AF529359 98 TCE-contaminated site clone, AF529131 100 TCE-contaminated site clone, AY133066 sp. RCB, AY032610 85 limneticum, Y17060 australiensis, AY007722 polluted river biofilm clone Spb272, AJ422172 alkane-degrading denitrifying bacterium OcN1, AF331976 Dechloromonas sp. JJ, AY032611 Dechloromonas sp. SIUL, AF170356 95 TCE-contaminated site clone, AF529339 Dechloromonas sp. SIUL, AJ318917 98 Dechloromonas sp. LT-1, AY124797 "Thiobacillus" Q sp. LMD 81.11, AJ289884 Dechloromonas- EBPR reactor clone PHOS-HE23, AF314420 Ferribacterium- 100 activated sludge clone UCT N141, AY062126 Quadricoccus- activated sludge clone UCT N123, AY064177 lineage Dechloromonas sp. MissR, AF170357 perchlorate-reducing bacterium EAB2, AY265879 91.8% perchlorate-reducing bacterium PMC, AY265878 drinking water biofim isolate B2, AF035048 Dechloromonas sp. PC1, AY126452 perchlorate-reducing bacterium RC1, AY265876 100 perchlorate-reducing bacterium Rick74, AF444789 perchlorate-reducing bacterium Elsa1, AF444790 perchlorate-reducing bacterium MLC33, AF444791 100 Dechloromonas sp. JM, AF323489 Dechloromonas sp. HZ, AF479766 Dechloromonas agitata, AF047462 perchlorate-reducing bacterium EAB1, AY265877 94 Dechloromonas sp. CL, AF170354 Dechloromonas sp. NM, AF170355 P+ sludge clone SBRH147, AF204246 Azonexus fungiphilus, AF011350 100 betaproteobacterial clone KD2-110, AY188298 anaerobic consortium TCB-transforming microbial consortium clone SJA-109, AJ009484 clone SJA-109 lineage 97.9% 100 betaproteobacterial strain 51885, AF227840 oral strain A08KA lineage human subgingival plaque strain A08KA, AY005031 10% 99.7%