Table 1

3MST protects E. coli against different classes of antibiotics. A representative list of chemicals from the Phenotype MicroArray that preferentially suppressed the growth of 3MST-deficient cells (ΔsseA). Major classes of antibiotics are indicated by type (column 4). Negative numbers indicate the relative growth inhibition of the 3MST-deficient strain compared with that of the wt strain (as provided by Biolog Inc.) (fig. S4). The minimum inhibitory concentration drop for ΔsseA, as determined by Biolog, for two representative antibiotics, norfloxacin and troleandomycin, is 12- and 7-fold, respectively.

ΔsseA inhibitionChemicalBiological effectType
–265NovobiocinDNA intercalationQuinolone
–212NorfloxacinDNA intercalationQuinolone
–183Nalidixic acidDNA intercalationQuinolone
–117Oxolinic acidDNA intercalationQuinolone
–295AcriflavineDNA intercalationAcridine
–1429-AminoacridineDNA intercalationAcridine
–93ProflavineDNA intercalationAcridine
–372TrifluoperazineDNA intercalationPhenothiazine
–262PromethazineDNA intercalationPhenothiazine
–251ChlorpromazineDNA intercalationPhenothiazine
–421StreptomycinProtein synthesisAminoglycoside
–179ApramycinProtein synthesisAminoglycoside
–520TylosinProtein synthesisMacrolide
–498OleandomycinProtein synthesisMacrolide
–468ErythromycinProtein synthesisMacrolide
–294JosamycinProtein synthesisMacrolide
–235SpiramycinProtein synthesisMacrolide
–203TroleandomycinProtein synthesisMacrolide
–136ChloramphenicolProtein synthesisAmphenicol
–271Fusidic acidProtein synthesisSteroid
–352Rifamycin SVRNA synthesisAnsamycin
–212TrimethoprimDNA-RNA synthesisAntifolate
–4292,4-Diamino-6,7-diisopropylpteridineDNA-RNA synthesisAntifolate
–231Polymyxin BMembranePolymyxin
–102ColistinMembranePolymyxin
–198VancomycinCell wallGlycopeptide
–201CefsulodinCell wallCephalosporin
–160CephalothinCell wallCephalosporin
–159CefoperazoneCell wallCephalosporin
–346OxacillinCell wallLactam
–227NafcillinCell wallLactam
–216PhenethicillinCell wallLactam
–186Penicillin GCell wallLactam
–182CloxacillinCell wallLactam
–171MoxalactamCell wallLactam
–164CarbenicillinCell wallLactam