Bacteria----|
(Domain)    |---Proteobacteria (Phylum BXII)
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            |      |---Alphaproteobacteria (Class I)
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            |      |      |---Rhizobiales (Order VI)
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            |      |             |---Rhizobiaceae (Family I)
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            |      |             |      |---Rhizobium (Genus I)          
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            |      |             |      |---Sinorhizobium (Genus VII)       
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            |      |             |---Phyllobacteriaceae (Family V)
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            |      |             |      |---Mesorhizobium (Genus VI)        
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            |      |             |---Bradyrhizobiaceae (Family VIII)
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            |      |                    |---Bradyrhizobium (Genus I)        
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            |      |---Betaproteobacteria (Class II)
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            |      |      |---Burkholderiales (Order I)
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            |      |      |      |---Burkholderiaceae (Family I)
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            |      |      |      |      |---Burkholderia (Genus I)          
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            |      |      |      |      |---Ralstonia (Genus VIII)          
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            |      |      |      |---Alcaligenaceae (Family III)
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            |      |      |             |---Bordetella (Genus III)          
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            |      |      |---Neisseriales (Order IV)
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            |      |             |---Neisseriaceae (Family I)
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            |      |                    |---Chromobacterium (Genus IV)       
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            |      |---Gammaproteobacteria (Class III)
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            |      |      |---Xanthomonadales (Order III)
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            |      |      |      |---Xanthomonadaceae (Family I)
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            |      |      |             |---Xanthomonas (Genus I)           
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            |      |      |---Psudomonadales (Order IX)
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            |      |      |      |---Pseudomonadaceae (Family I)
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            |      |      |             |---Pseudomonas (Genus I)           
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            |      |      |---Vibrionales (Order XI)
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            |      |      |      |---Vibrionaceae (Family I)
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            |      |      |             |---Vibrio (Genus I)                
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            |      |      |---Aeromonadales (Order XII)
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            |      |      |      |---Aeromonadaceae (Family I)
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            |      |      |             |---Aeromonas (Genus I)             
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            |      |      |---Enterobacteriales (Order XIII)
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            |      |             |---Enterobacteriaceae (Family I)
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            |      |                    |---Escherichia (Genus I)           
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            |      |                    |---Citrobacter (Genus X)           
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            |      |                    |---Edwardsiella (Genus XI)         
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            |      |                    |---Erwinia (Genus XIII)            
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            |      |                    |---Pantoea (Genus XXIII)           
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            |      |                    |---Photorhabdus (Genus XXVI)       
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            |      |                    |---Salmonella (Genus XXXIV)        
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            |      |                    |---Shigella (Genus XXXVII)         
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            |      |                    |---Sodalis (Genus XXXVIII)         
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            |      |                    |---Yersinia (Genus XLIII)          
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            |      |---Deltaproteobacteria (Class IV)
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            |             |---Desulfovibrionales (Order II)
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            |                    |---Desulfovibrionaceae (Family I)
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            |                           |---Desulfovibrio (Genus I)         
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            |---Chlamydiae (Phylum BXVI)
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                   |---Chlamydiae (Class I)
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                          |---Chlamydiales (Order I)
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                                 |---Chlamydiceae (Family I)
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                                 |      |---Chlamydia (Genus I)             
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                                 |      |---Chlamydophila (Genus II)        
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                                 |---Parachlamydiceae (Family II)
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                                        |---Parachlamydia (Genus I)