TABLE 3.
Comparison of the Htx and Phn proteins in P. stutzeri with each other and with the Phn proteins of E. coli
| Phn protein | Closest homolog of predicted product (% identity)a | % Identity to E. coli Phn homologb | Htx protein | Closest homolog of predicted product(s) (% identity) | % Identity to E. coli Phn homologb | Phn and Htx homologs of P. stutzeri WM88c | % Identity between Phn and Htx proteins | Proposed function of Phn and Htx proteins |
|---|---|---|---|---|---|---|---|---|
| PhnD | P. aeruginosa (PAO1) PhnD (73.7) | 54.0 | HtxB | Nostoc sp. PhnD, phosphonate binding protein (25.7) | 18.1 | PhnD/HtxB | 20.3 | Phosphonate binding protein of ABC transporter |
| PhnE | P. aeruginosa (PAO1) PhnE (85.9) | 69.2 | HtxC | Bradyrhizobium japonicum PhnE (40.1) | 32.6 | PhnE/HtxC | 33.3 | Phosphonate transport permease |
| HtxE | Bacillus anthracis PhnE (41.3) | 26.8 | PhnE/HtxE | 29.8 | ||||
| PhnC | P. syringae (pv. tomato) PhnC (80.8) | 58.3 | HtxD | E. coli PhnC (44.7) | 44.7 | PhnC/HtxD | 20.3 | Phosphonate binding protein of ABC transporter |
| PhnF | P. aeruginosa (PAO1) probable transcriptional regulator (67.9) | 41.1 | —d | Transcriptional regulator (GntR family) | ||||
| PhnG | P. syringae (pv. tomato) PhnG (73.2) | 43.9 | HtxF | Sinorhizobium sp. PhnG (33.3) | 21.4 | PhnG/HtxF | 22.6 | Phosphonate metabolism protein |
| PhnH | P. syringae (pv. tomato) PhnH (61.0) | 33.2 | HtxG | E. coli PhnH (32.6) | 32.6 | PhnH/HtxG | 25.4 | Phosphonate metabolism protein |
| PhnI | P. syringae (pv. tomato) PhnI (80.8) | 62.9 | HtxH | Mesorhizobium loti PhnI (45.2) | 43.6 | PhnI/HtxH | 42.6 | Phosphonate metabolism protein |
| PhnJ | P. syringae (pv. tomato) PhnJ (89.5) | 75.4 | HtxI | E. coli PhnJ (53.7) | 53.7 | PhnJ/HtxI | 53.0 | Phosphonate metabolism protein |
| PhnK | P. aeruginosa (PAO1) putative ATP binding component (86.3) | 65.2 | HtxJ | Agrobacterium tumefaciens PhnK (40.2) | 32.3 | PhnK/HtxJ | 30.5 | Phosphonate ATP binding protein |
| PhnL | P. aeruginosa (PAO1) putative ATP binding component (86.0) | 58.5 | HtxK | M. loti PhnL (52.0) | 42.6 | PhnL/HtxK | 42.6 | Phosphonate ATP binding protein |
| PhnM | P. syringae (pv. tomato) PhnM (71.6) | 56.5 | HtxL | Rhizobium luguminosarum PhnM (36.6) | 34.7 | PhnM/HtxL | 35.0 | Phosphonate metabolism protein |
| PhnN | P. syringae (pv. tomato) PhnN (62.0) | 39.4 | HtxM | S. meliloti PhnN (47.3) | 41.6 | PhnN/HtxM | 37.4 | Phosphonate metabolism accessory protein |
| PhnP | P. syringae (pv. tomato) PhnP (71.5) | 46.0 | HtxN | P. aeruginosa conserved hypothetical protein (53.0); P. syringae PhnP (51.0) | 45.9 | PhnP/HtxN | 49.0 | Phosphonate metabolism accessory protein |
a
Closest homologs were determined with FASTA searches of the predicted amino acid sequences against sequences in the nonredundant Swiss Protein Database on 15 May 2003.
b
Pairwise sequence alignments were performed with the predicted amino acid sequences of the P. stutzeri Phn or Htx protein with the E. coli Phn homologs.
c
Pairwise sequence alignments were performed with the predicted amino acid sequences of the P. stutzeri Phn or Htx proteins.
d
The Phn homolog was absent from the htx sequence.