Table 1.
Promoter activity of E. amylovora 273 hrpA measured by the GFP promoter-reporter fusion plasmid (phrpA) in HIM and HIM supplemented with phenolic compounds and their analogs
| Strain and phenolic compounda | MFI (avg ±SD)b at: |
|
|---|---|---|
| 6 h | 9 h | |
| 273(pPROBE-gfp[AAV]) | 1.4 ± 0.2 | 1.2 ± 0.1 |
| 273(phrpA) | ||
| DMSO | 1,229.4 ± 39.2 | 1,024.3 ± 52.9 |
| TS24, trans-2-carboxycinnamic acid | 361.1 ± 76.1* | 332.2 ± 19.6* |
| TS30, methyl trans-cinnamate | 674.8 ± 252.1 | 668.5 ± 31.2* |
| TS32, cinnamyl alcohol | 681.6 ± 217.9 | 784.0 ± 53.3* |
| TS27, trans-4-aminocinnamic acid | 255.6 ± 7.4* | 132.1 ± 8.5* |
| TS26, trans-4-mercaptocinnamic acid | 159.7 ± 22.0* | 44.7 ± 2.7* |
| TS29, trans-4-formlycinnamic acid | 285.1 ± 40.8* | 218.3 ± 9.9* |
| TS28, trans-4-nitrocinnamic acid | 14.4 ± 16.9* | 4.0 ± 0.3* |
| TS101, methyl para-coumate | 1,443.4 ± 49.4* | 1,227.8 ± 41.6* |
| TS102, trans-4-hydroxycinnamaide | 1,134.0 ± 36.7 | 766.4 ± 94.8 |
| TS103, trans-4-hydroxycinnamohydroxamic acid | 206.9 ± 3.9* | 168.2 ± 24.9* |
| TS104, para-coumaryl alcohol | 814.7 ± 55.2* | 556.9 ± 40.3* |
| TS105, trans-2-(4-methoxyphenyl)-1-cyclopropanecarboxylic acid | 345.3 ± 11.9* | 200.2 ± 11.0* |
| TS106, ethyl trans-2-(4-hydroxyphenyl)-1-cyclopropanecarboxylate | 1,289.3 ± 46.5 | 1,110.9 ± 67.5 |
| TS107, trans-2-(4-hydroxyphenyl)-1-cyclopropanecarboxylic acid | 1,464.3 ± 76.5* | 1,348.0 ± 82.6* |
| TS108, trans-4-phenylcinnamic acid | 173.7 ± 7.9* | 79.4 ± 1.8* |
| TS109, trans-4-chlorocinnamide | 172.9 ± 20.5* | 90.6 ± 12.0* |
| TS110, trans-4-fluorocinnamic acid | 279.2 ± 5.3* | 152.4 ± 0.7* |
| TS111, trans-4-bromocinnamic acid | 102.8 ± 23.5* | 61.8 ± 4.2* |
| TS112, trans-4-dimethylaminocinnamic acid | 87.0 ± 4.0* | 37.3 ± 3.7* |
| DMSO | 1,476.7 ± 63.8 | 1,649.1 ± 96.9 |
| TS6, ortho-coumaric acid | 443 ± 16.9* | 437.8 ± 21.1* |
| TS1, trans-cinnamic acid | 471.2 ± 12.6* | 432.6 ± 17.8* |
| TS4, para-coumaric acid | 920.6 ± 29.1* | 993.8 ± 43.3* |
| TS5, meta-coumaric acid | 1,212 ± 47.6 | 1,439.1 ± 97.9 |
| TS33, salicylic acid | 49.8 ± 13.9* | 34.3 ± 4.2* |
| TS34, benzoic acid | 48.1 ± 5.4* | 32.6 ± 1.9* |
| DMSO | 1,242.1 ± 27.0 | 1,672.5 ± 126.0 |
| TS122, ethyl trans-2-(4-hydroxyphenyl)-ethenylsulfonate | 2,042.8 ± 20.7* | 2,900.6 ± 120.1* |
| TS123, trans-2-(4-hydroxyphenyl)ethenylsulfonic acid tetra(n-butyl)ammonium salt | 1,073.4 ± 107.7 | 1,377.3 ± 81.1 |
| TS124, trans-4-hydroxymethylcinnamic acid | 419.8 ± 12.2* | 444.3 ± 11.4* |
| TS125, trans-4-methoxycinnamohydroxamic acid | 215.5 ± 6.5* | 230.0 ± 4.4* |
| TS126, trans-4-methoxycinnamyl alcohol | 386.9 ± 19.4* | 401.4 ± 10.8* |
| TS127, trans-3-indoleacrylohydroxamic acid | 91.4 ± 4.9* | 102.7 ± 0.5* |
| TS128, trans-4-bromocinnamohydroxamic acid | 17.6 ± 2.8* | 5.7 ± 2.2* |
| TS129, trans-2-hydroxycinnamohydroxamic acid | 187.9 ± 1.2* | 181.0 ± 0.7* |
| TS130, trans-3-hydroxycinnamohydroxamic acid | 431.4 ± 4.1* | 491.0 ± 10.2* |
| TS131, trans-3,4-dihydroxycinnamohydroxamic acid | 1,057.5 ± 41.2* | 1,515.1 ± 39.1 |
| TS132, trans-cinnamohydroxamic acid | 145.7 ± 1.2* | 147.8 ± 4.2* |
| TS133, trans-3-(4-hydroxyphenyl)acrylohydrazide | 1,716.5 ± 33.1* | 2,780.9 ± 58.5* |
| TS136, phenylpropiolic acid | 261.7 ± 1.0* | 307.0 ± 9.3* |
| TS134, benzhydroxamic acid | 679.0 ± 12.7* | 921.6 ± 10.3* |
| TS135, salicylhydroxamic acid | 124.7 ± 7.7* | 147.8 ± 4.3* |
| DMSO | 1,068.6 ± 170.9 | 1,157.8 ± 58.7 |
| TS8, hydrocinnamic acid | 395.9 ± 16.0* | 342.0 ± 11.7* |
| TS9, phenoxyacetic acid | 342.7 ± 24.8* | 269.9 ± 15.2* |
| TS10, trans-2-phenylcyclopropane-1-carboxylic acid | 336.7 ± 28.1* | 293.0 ± 4.7* |
| TS13, trans-3-(3-pyridyl)acrylic acid | 468.3 ± 7.7* | 245.7 ± 3.1* |
| TS35, 3-(2-naphthyl)acrylic acid | 178.9 ± 9.7* | 89.0 ± 6.2* |
| TS12, trans-3-indoleacrylic acid | 33.7 ± 8.9* | 47.9 ± 6.9* |
| TS11, trans-3-(2-thienyl)acrylic acid | 230.1 ± 5.8* | 167.3 ± 8.2* |
| TS15, trans-2-methoxycinnamic acid | 342.6 ± 7.0* | 255.1 ± 1.7* |
| TS18, trans-2-methylcinnamic acid | 303.8 ± 8.7* | 262.5 ± 9.3* |
| TS21, trans-2-chlorocinnamic acid | 225.7 ± 35.8* | 192.7 ± 8.6* |
| TS14, trans-3-(4-imidazolyl)acrylic acid | 874.6 ± 23.1* | 839.2 ± 17.6* |
| TS2, 2,4-dihydroxycinnamic acid | 1,365.3 ± 104.9 | 1,479.8 ± 72.9* |
| TS7, 3-(4-hydroxyphenyl)propionic acid | 1,093.1 ± 62.8 | 1,211.0 ± 58.7 |
| TS23, trans-4-chlorocinnamic acid | 171.8 ± 7.7* | 125.8 ± 3.9* |
| TS17, trans-4-methoxycinnamic acid | 132.5 ± 5.5* | 76.4 ± 2.7* |
| TS20, trans-4-methylcinnamic acid | 208.5 ± 2.7* | 145.4 ± 3.7* |
| TS3, 3,4-dihydroxycinnamic acid | 783.4 ± 80.2* | 787.3 ± 25.2* |
| TS22, trans-3-chlorocinnamic acid | 332.9 ± 16.9* | 238.3 ± 8.7* |
| TS16, trans-3-methoxycinnamic acid | 265.3 ± 24.4* | 198.5 ± 20.0* |
| TS19, trans-3-methylcinnamic acid | 311.5 ± 18.6* | 251.6 ± 13.3* |
| DMSO | 1,120.4 ± 44.4 | 1,499.8 ± 30.9 |
| TS25, trans-cinnamamide | 1,034.7 ± 12.5 | 1,378.1 ± 14.6 |
| TS31, trans-4-carboxycinnamic acid | 257.7 ± 14.3* | 187.1 ± 8.4* |
| TS100, ethyl trans-2-(4-methoxyphenyl)-1-cyclopropanecarboxylate | 1,090.5 ± 20.6 | 1,406.4 ± 9.0 |
| TS113, trans-4-trifluoromethylcinnamic acid | 172.1 ± 4.7* | 199.2 ± 11.1* |
| TS114, diethyl trans-2-(4-hydroxyphenyl)-vinylphosphonate | 1,371.3 ± 16.1* | 2,023.3 ± 28.9* |
| TS115, trans-2-(4-hydroxyphenyl)-vinylphosphonic acid | 1,176.6 ± 56.6 | 1,636.9 ± 53.3 |
| TS117, para-coumarylamine | 897.6 ± 48.9* | 1,372.6 ± 48.6 |
| TS118, N-(4-methoxycinnamyl)phthalimide | 919.8 ± 34.4 | 1,240.0 ± 29.7 |
| TS119, trans-4-methoxycinnamylamine | 285.9 ± 44.2* | 570.0 ± 68.4* |
| TS120, ethyl trans-2-(4-methoxyphenyl)-ethenylsulfonate | 982.1 ± 12.8 | 1,338.3 ± 75.4 |
| TS121, trans-2-(4-methoxyphenyl)ethenylsulfonic acid tetra(n-butyl)ammonium salt | 977.1 ± 20.4 | 1,336.3 ± 79.2 |
| DMSO | 1,100.1 ± 30.8 | 1,351.9 ± 62.4 |
| TS160, trans-2-methylcinnamohydroxamic acid | 122.7 ± 1.9* | 95.7 ± 3.7* |
| TS161, trans-3-(2-thienyl)acrylhydroxamic acid | 132.4 ± 13.2* | 145.0 ± 11.7* |
| TS165, trans-2-[(4′-benzylcarbonyl]phenylcyclopropane-1-carboxylic acid | 292.8 ± 17.1* | 229.4 ± 15.0* |
| DMSO | 1,132.3 ± 93.6 | 1,295.0 ± 86.5 |
| TS137, N-methyl-4-hydroxycinnamamide | 1,064.1 ± 99.3 | 1,121.1 ± 52.1 |
| TS138, N-(2-hydroxyethyl)-4-hydroxycinnamamide | 1,474.5 ± 30.4* | 1,907.0 ± 39.8* |
| TS139, 3-phenylpropionohydroxamic acid | 306.3 ± 11.9* | 286.3 ± 10.0* |
| TS140, trans-4-phenylcinnamohydroxamic acid | 101.7 ± 17.1* | 82.8 ± 4.3* |
| TS141, trans-4-fluorocinnamohydroxamic acid | 167.6 ± 4.7* | 119.0 ± 7.1* |
| TS142, trans-4-methylcinnamohydroxamic acid | 126.2 ± 5.6* | 106.0 ± 13.6* |
| TS143, 2-phenoxyacetohydroxamic acid | 228.7 ± 4.6* | 178.5 ± 27.1* |
| TS144, 4-hydroxybenzoic acid | 434.4 ± 22.1* | 424.7 ± 24.8* |
| TS145, 3-hydroxybenzoic acid | 559.4 ± 23.6* | 529.9 ± 32.0* |
| TS146, trans-4-formylcinnamohydroxamic acid | 414.3 ± 31.6* | 435.2 ± 36.2* |
| TS147, trans-4-hydroxymethylcinnamohydroxamic acid | 688.6 ± 39.2* | 746.8 ± 96.3* |
a
HIM (hrp-inducing minimal medium) was supplemented with 100 μM concentrations of the indicated compounds. The compounds were assayed two different times, with HIM supplemented with DMSO as the control treatment for each set of experiments.
b
E. amylovora 273 cells carrying the GFP reporter phrpA were used in this study. The promoter activities at 6 and 9 h of bacterial growth were determined. GFP mean fluorescence intensity (MFI) was determined for gated populations of bacterial cells by flow cytometry. Values are representative of two experiments, and three replicates were used for each experiment. *, the value is statistically significantly different from that for the DMSO control (P < 0.05, Student's t test).