Table 1.

Resistance-nodulation-division (RND) family multidrug efflux transporters in Gram-negative bacteria and mycobacteria reported or further characterized since 2003

Species	Efflux system component^a			Regulator (Family)	Substrates^b	References
	MFP	RND	OMP
Acinetobacter baumannii	AdeI	AdeJ	AdeK	?	AO, BL, CM, EM, FQ, FU, LC, NO, PY, RF, SA, SDS, TC, TM	[286, 296]
Acinetobacter genospecies 3	AdeD	AdeF	?	?	AM, CM, CP, CT, EB, EM, MP, RF, TC	[287, 296]
	AdeX	AdeY	AdeZ	?	?	[288, 296]
Acinetobacter genospecies UT13	Unknown	Unknown	AdeC	?	?	[733]
Aeromonas hydrophilia	AheA	AheB	AheC	AheR (TetR)	BC, BL, EM, FU, LC, PR, TC, TM, TT	[223]
Bacteroides fragilis	BmeA1-16	BmeB1-16	BmeC1-16	Varied, e.g., BmeR5 (TetR)	BL, CP, EB, MD, SDS	[384, 389, 390]
Brucella suis	BepD	BepE	BepC	BepR (TetR)	AM, BL, CAB, CV, DC, EB, EM, FQ, SDS, TC	[349, 350]
	BepF	BepG	BepC	?	DC, NA	[350]
Burkholderia cenocepacia	CeoA	CeoB	OpcM	CeoR (LysR)	CM, FQ, TMP	[325]
	?	ORF2	?	?	EB, FQ, SM, TPP	[324]
Burkholderia glumae	ToxG	ToxH	ToxI	ToxR (LysR)	TF	[610]
Burkholderia pseudomallei	BpeA	BpeB	OprB	BpeR (TetR)	AC, AG, EM	[326, 327]
	BpeE	BpeF	OprC	BpeT (LysR)	CM, TM	[328]
Campylobacter jejuni	CmeD	CmeE	CmeF	?	AO, AP, CAB, EB, PM, SDS, TR	[371, 373]
Chromohalobacter spp.	?	?	HrdC	?	BL, CM, EB, OS, TC	[734]
Enterobacter aerogenes	EefA	EefB	EefC	?	CM, CP, EM, TC	[182, 735]
Enterobacter cloacae	AcrA	AcrB	TolC	AcrR (TetR), RamA (MarA)	AC, AG, BL, CL, CM, CP, CV, DC, EM, LC, LZ, SDS, SXT, TC, TG	[736]
Erwinia amylovora	AcrA	AcrB	?	AcrR (TetR)	BB, CV, EB, MB, PH, SDS	[596]
Escherichia coli	OqxA (plasmidborne)	OqxB (plasmidborne)	?	ORF68 (plasmidborne)	CM, CP, EB, OQ	[154–156]
Haemophilus influenzae	AcrA	AcrB	?	AcrR (TetR)	AP	[321, 737]
Helicobacter pylori	CznB	CznA	CznC	?	MS	[382]
	HefB	HefC	HefA	?	CM, CR, CX, EB, GM, ML, NO, TC	[378, 380, 738]
Klebsiella pneumoniae	AcrA	AcrB	AcrR	AcrR (TetR), RamA (MarA)	AC, CM, EB, EM, NA, NF, NO, TC, TG	[187, 190, 739]
	EefA	EefB	EefC	?	Inorganic acid	[191]
Morganella morganii	AcrA	AcrB	?	AcrR (TetR)	AC, CM, EB, EM, NA, NO, SDS, TC, TG, TM	[269]
Mycobacterium tuberculosis	?	MmpL7	?	?	INH	[518]
Neisseria gonorrhoeae	FarA	FarB	MtrE	FarR (MarR)	FA	[740]
Pasteurella multocida	?	?	PM0527	?	AO, CT, CV, EB, EM, LC, NO, RF, SDS, TM	[741]
	?	?	PM1980	?	CT, RF, VC.	[741]
Proteus mirabilis	AcrA	AcrB	TolC	?	AC, AP, CM, CP, MI, SAM, SDS, TC, TG, TM	[267]
Pseudomonas aeruginosa	MexA	MexB	OprM	AmrR, MexR (MarR), NalC (TetR), NalD (TetR)	AC, AO, AG, BL, MC, FQ, NO, OS, SF, TC, TG, TR	[1, 228, 623, 624, 626]
	MexM	MexN	OprM	?	CM, TP	[264]
	MexP	MexQ	OpmM	?	MC, FQ	[264]
	MexV	MexW	OprM	?	AC, CM, EB, EM, FQ, TC	[262]
	TriAB	TriC	OpmH	?	TR	[123]
Pseudomonas fluorescens	EmhA	EmhB	EmhC	?	Polycyclic aromatic hydrocarbons, CM, NA	[275, 276]
Pseudomonas stutzeri	TbtA	TbtB	TbtM	?	CM, NA, OS, SF, TT	[278]
Pseudomonas syringae	MexA	MexB	OprM	PmeR (TetR)	AC, AG, AO, BB, BC, CM, CV, DA, EB, EM, FQ, FU, NA, NT, RG, TC, TM, TPP	[684]
	PseB	PseC	PseA	GacS/GacA	AC, EM, TC	[590]
Ralstonia solanacearum	AcrA	AcrB	?	AcrR (TetR)	AC, AP, BB, EB	[595]
Salmonella Typhimurium	MdtA	MdtBC	?	?	DC, NO, SDS	[172]
	MsdA	MsdB	MsdC, TolC	?	DC, NO, SDS	[172]
Serratia marcescens	SdeA	SdeB	HasF	SdeR (MarA)	CM, EB, FQ, OS, SDS	[198, 199]
	SdeC	SdeDE	?	?	NO	[198, 742]
	SdeX	SdeY	?	?	AC, BAC, EM, NF, RG, TC	[197]
Serratia spp.	ZrpAD	ZrpB	ZrpC?	PigZ (TetR)	?	[206]
Stenotrophomonas maltophilia	SmeG	SmeH	?	Smlt3169 (TetR)	?	[306]
	SmeI	SmeJK	?	?	AG, CP, TC	[306]
	SmeM	SmeN	?	?	?	[306]
	SmeO	SmeP	?	Smlt3926 (TetR)	?	[306]
	SmeV	SmeW	SmeX	Smlt1827 (LysR)	?	[306]
	SmeY	SmeZ	?	Smlt2199-2130	AG	[306]
Vibrio cholerae	VexA	VexB	?	VexR (TetR)	MDR	[207–209]
	VexC/BreA	VexD/BreB	?	VexR/BreR (TetR)	BS	[207–209]
	VexE	VexF	TolC	?	BC, BS, DC, EB, EM, NF, NO, SDS, TC, TM	[209]
Vibrio parahaemolyticus	VmeA (VP1091)	VmeB (VP1092)	VpoC (VP0425)	?	AC, BL, CP, CV, DC, EB, EM, NF, RG, SDS, TC, TM	[743]

MFP=membrane fusion protein; OMP=outer membrane protein; RND=resistance-nodulation-division.

AC=acriflavine; AG=aminoglycosides; AM=amikacin; AO=acridine orange; AP=ampicillin; BC=benzalkonium chloride; BL=β-lactams; BS=bile salts; CAB=cetyltrimethylammonium bromide; CL= cholate; CM=chloramphenicol; CP=ciprofloxacin; CR=clarithromycin; CT=ceftazidime; CV=crystal violet; CX=cefotaxime; DA=daunorubicin, DC=deoxycholate; EB=ethidium bromide; EM=erythromycin; FA=fatty acids; FQ=fluoroquinolones; FU=fusidic acid; GM=gentamicin; INH=isoniazid; LC=lincosamides; LZ=linezolid; MB=methylene blue; MC=macrolides; MD=metronidazole; MI= minocycline; MP=meropenem; MS=metal salts; NA=nalidixic acid; NF=norfloxacin; NO=novobiocin; NT=nitrofurantoin OQ=olaquindox; OS=organic solvents; PH=Phloretin; PM=polymyxin B; PR=pristinamycin; PY=pyronine; RF=rifampin; RG=rhodamine 6G; SAM= ampicillin-sulbactam; SDS=sodium dodecyl sulphate; SA=safranin; SF=sulfonamides; SM=streptomycin; SXT=trimethoprim sulfamethoxazole; TC=tetracyclines; TF=toxoflavin; TG=tigecycline; TM=trimethoprim; TP=thiamphenicol; TPP=tetraphenylphosphonium; TR=triclosan; TT=tributyltin; VC=vancomycin; ?=the efflux components or regulators remain unknown or no genes linked to the transporter structural gene(s) are identified.