TABLE 2 .
Genes identified by Tn-seq exhibiting strong mutant hypersensitivity to tobramycina
| Locus | Gene | Function | No. of normalized reads (no. of hits with reads)b |
Selection ratiob | Previously identifiedc | No. of mutants testedd | MICe | ||
|---|---|---|---|---|---|---|---|---|---|
| Pregrowth | Growth without Tob | Growth with Tob | |||||||
| None (PAO1) | 1.0 | ||||||||
| PA3303 (control) | 1,888 (17) | 2,062 (20) | 1,703 (20) | 0.83 | 1 | 1.0 | |||
| PA0392 | Conserved hypothetical | 644 (5) | 1,374 (5) | 0 (0) | 0 | No | 2f | 0.25 | |
| PA4077 | Transcriptional regulator | 1,572 (3) | 1,230 (3) | 0 (0) | 0 | No | 1f | 0.25 | |
| PA5199 | amgS | Two-component sensor | 764 (18) | 663 (20) | 0 (0) | 0 | Yes | 0.125 | |
| PA5366 | pstB | Phosphate transport | 1,748 (8) | 761 (8) | 0 (0) | 0 | Yes | 0.25 | |
| PA5200 | amgR | Two-component response regulator | 752 (9) | 396 (12) | 2 (1) | 0.00 | Yes | 0.063 | |
| PA0016 | trkA | Potassium uptake | 1,089 (16) | 823 (16) | 5 (2) | 0.01 | Yes | 0.25 | |
| PA4942 | hflK | Protease subunit | 2,436 (14) | 2,104 (16) | 30 (2) | 0.01 | Yes | 0.25 | |
| PA3014 | faoA | Fatty acid oxidation | 1,465 (23) | 1,227 (27) | 56 (5) | 0.05 | No | 5 | 0.25 |
| PA4398 | Two-component sensor | 862 (19) | 633 (19) | 30 (2) | 0.05 | Yes | 0.25 | ||
| PA5528 | Hypothetical | 2,363 (12) | 2,839 (13) | 161 (4) | 0.06 | Yes | 0.125 | ||
| PA1805 | ppiD | Peptidyl-prolyl isomerase | 3,920 (29) | 4,583 (29) | 397 (12) | 0.09 | No | 5 | 0.25 |
| PA3016 | Hypothetical | 1,630 (9) | 840 (8) | 87 (1) | 0.10 | Yes | 0.125 | ||
| PA4223 | Transport | 638 (19) | 790 (19) | 106 (10) | 0.13 | No | 3 | 0.25 | |
| PA4960 | Amino acid metabolism | 916 (15) | 507 (17) | 80 (2) | 0.16 | No | 2 | 0.25 | |
| PA0374 | ftsE | Cell division | 4,583 (8) | 4,366 (8) | 705 (4) | 0.16 | No | 3 | 0.125g |
| PA3013 | foaB | Fatty acid oxidation | 3,632 (29) | 2,925 (32) | 485 (14) | 0.17 | Yes | 0.25 | |
| PA5471 | Hypothetical | 655 (8) | 755 (8) | 129 (4) | 0.17 | Yes | 0.25 | ||
| PA0502 | Biotin biosynthesis | 1,131 (9) | 627 (9) | 108 (3) | 0.17 | No | 1 | 0.25 | |
| PA3194 | edd | Carbohydrate metabolism | 253 (10) | 161 (11) | 29 (5) | 0.18 | No | 1 | 0.125 |
| PA1775 | cmpX | Cytoplasmic membrane protein | 1,670 (13) | 747 (11) | 134 (7) | 0.18 | No | 3 | 0.25 |
| PA0427 | oprM | Multidrug efflux | 1,877 (15) | 1,427 (15) | 298 (6) | 0.21 | Yes | 0.25 | |
| PA4222 | Transport | 551 (16) | 333 (18) | 74 (6) | 0.22 | No | 2 | 0.25 | |
| PA5369 | pstS | Phosphate transport | 1,037 (10) | 631 (9) | 164 (3) | 0.26 | No | 3 | 0.25g |
| PA2018 | mexY | Multidrug efflux | 3,025 (45) | 2,761 (46) | 811 (40) | 0.29 | Yes | 0.25 | |
| PA5285 | Hypothetical | 1,293 (4) | 1,559 (4) | 466 (4) | 0.30 | No | 4 | 0.25 | |
| PA2604 | Conserved hypothetical | 2,736 (8) | 2,162 (9) | 649 (8) | 0.30 | No | 3 | 0.25 | |
| PA2019 | mexX | Multidrug efflux | 2,403 (20) | 2,488 (21) | 930 (18) | 0.37 | Yes | 0.25 | |
| PA4050 | pgpA | Phospholipid biosynthesis | 1,931 (6) | 1,214 (7) | 483 (4) | 0.40 | No | 3 | 0.125 |
a
Genes whose mutation caused a 4-fold or greater MIC change are listed.
b
See text for method of calculation. Tob, tobramycin.
c
Reference 7.
d
Number of independent mutants tested. Thirty-four of the 42 mutants examined were confirmed by resequencing, including at least one representative for each gene.
e
MIC values (in micrograms per milliliter) for representative mutants as measured in this study or in reference 7.
f
Includes one deletion mutant.
g
Phenotype possibly due to expression of hybrid proteins.