. 2000 Jun;64(2):354–411. doi: 10.1128/mmbr.64.2.354-411.2000

TABLE 11.

Classification of secondary carriers according to substrate specificity^a

Substrate	TC no.	Family	Energy source or mechanism	Organismal group
I.C. Inorganic cations: monovalent
Ag⁺ (efflux)	2.A.6.1.3	RND	Ag⁺:H⁺ antiport	B
H⁺	2.A.33.1.1	NhaA	H⁺:Na⁺ antiport	B
H⁺	2.A.34.1.1	NhaB	H⁺:Na⁺ antiport	B
H⁺	2.A.35.1.1	NhaC	H⁺:Na⁺ antiport	B
H⁺	2.A.36.1.3–5	CPA1	H⁺:Na⁺ antiport	B, Y, An, Pl
H⁺	2.A.37.1–5	CPA2	H⁺:Na⁺ antiport	B, Y
H⁺	2.A.38.1–4	Trk	H⁺:K⁺ symport	B, Y, Pl
H⁺	2.A.62.1.1	NhaD	H⁺:Na⁺ antiport	B
H⁺	2.A.63.1.1–3	CPA3	H⁺:Na⁺ or K⁺ antiport	B
H⁺ or OH⁻	2.A.29.3.1	MC	Uniport (?)	Mito
K⁺	2.A.19.3.2	CaCA	K⁺:Ca²⁺ symport; Na⁺ or H⁺ antiport	An
K⁺	2.A.30.1–3, 7	CCC	NaCl:KCl symport	An, Pl
K⁺	2.A.30.5–6	CCC	KCl symport	An
K⁺	2.A.36.4.1	CPA1	K⁺:H⁺ antiport	Y
K⁺	2.A.37.1–5	CPA2	K⁺:H⁺ antiport	B, Y
K⁺	2.A.38.1–4	Trk	K⁺ uptake (PMF?); K⁺:H⁺ or Na⁺ symport	B, Y, Pl
K⁺	2.A.63.1.1	CPA3	K⁺:H⁺ antiport	B
K⁺	2.A.72.1–3	KUP	K⁺ uptake (K⁺:H⁺ or K⁺:Na⁺ symport)	B, Y, Pl
Na⁺	2.A.30.1–3	CCC	NaKCl₂ symport	An
Na⁺	2.A.30.4.1	CCC	NaCl symport	An
Na⁺	2.A.30.7.1	CCC	NaKCl₂ symport	Pl
Na⁺	2.A.33.1.1	NhaA	Na⁺:H⁺ antiport	B
Na⁺	2.A.34.1.1	NhaB	Na⁺:H⁺ antiport	B
Na⁺	2.A.35.1.1	NhaC	Na⁺:H⁺ antiport	B
Na⁺	2.A.36.1–4	CPA1	Na⁺:H⁺ antiport	B, Y, An, Pl
Na⁺	2.A.37.2.1	CPA2	Na⁺:H⁺ antiport	B
Na⁺	2.A.38.3.1	Trk	Na⁺:K⁺ symport	Pl
Na⁺	2.A.62.1.1	NhaD	Na⁺:H⁺ antiport	B
Na⁺	2.A.63.1.2–3	CPA3	Na⁺:H⁺ antiport	B
NH₃ or NH₄⁺	2.A.49	Amt	Uniport?	B, A, Y, Pl, An
I.C. Inorganic cations: di- and trivalent
Al³⁺	9.A.17.2.1	MIT	Uniport?	Y
Ca²⁺	2.A.19.1–4	CaCA	H⁺ or Na⁺ antiport	B, Y (vacuolar), Pl, An
Cations, divalent; nonspecific	9.A.17.1–2	MIT	Uniport?	B, Y
Cations, divalent; nonspecific	2.A.3.10.1	APC	?	Y, F
Cations, divalent; nonspecific	2.A.5.1.2	ZIP	PMF (uptake)	Pl
Cations, divalent; nonspecific	2.A.55.1–2	Nramp	H⁺ symport	Y, An
Cd²⁺	2.A.4.1.1	CDF	PMF? (efflux)	B
Cd²⁺	2.A.4.2.2	CDF	PMF? (uptake)	Mito
Cd²⁺	2.A.6.1.2	RND	PMF (H⁺ antiport)	B
Cd²⁺	2.A.77.1.1	CadD	PMF (efflux)	B
Co²⁺	2.A.4.1.1–2	CDF	PMF? (efflux)	B
Co²⁺	2.A.4.2.1	CDF	PMF? (uptake)	Mito
Co²⁺	2.A.6.1.1–2	RND	H⁺ antiport	B
Co²⁺	9.A.17.1.1	MIT	PMF? (uptake) (uniport?)	B
Co²⁺	2.A.52.1.2	NiCoT	PMF? (uptake)	B
Cu²⁺	9.A.11.1.1	Ctr1	PMF? (uptake)	Y
Cu²⁺	9.A.12.1.1	Ctr2	PMF? (uptake)	Y, Pr, Pl, An
Fe²⁺	2.A.5.1.2	ZIP	PMF?	Y, Pl, An
Fe²⁺	9.A.17.1.1	MIT	PMF? (uptake)	B, A, Y
Fe²⁺	9.A.9.1.1	FeT	PMF? (uptake)	Y
Fe³⁺	9.A.10.1.1	OFeT	PMF? (uptake)	B, Y
Hg²⁺	9.A.2.1.1	MerTP	PMF? (uptake)	B
Hg²⁺	9.A.3.1.1	MerC	PMF? (uptake)	B
Mg²⁺	2.A.11.1.1	CitMHS	H⁺ symport	B
Mg²⁺	9.A.17.1.1	MIT	PMF? (uptake)	B
Mg²⁺	9.A.19.1.1	MgtE	?	B, A
Mn²⁺	2.A.3.1.15	APC	PMF? (efflux)	Y
Mn²⁺	2.A.5.2.1	ZIP	PMF (uptake)	Y
Mn²⁺	2.A.19.2.2	CaCA	PMF (H⁺ antiport)	Y
Mn²⁺	9.A.17.2.2	MIT	PMF? (efflux)	Y
Mn²⁺	2.A.55.1.1–2	Nramp	H⁺ symport (uptake)	B, A, Y, Pr, Pl, An
Ni²⁺	2.A.1.21.5	MFS	PMF? (efflux)	B
Ni²⁺	2.A.6.1.1	RND	H⁺ antiport	B
Ni²⁺	9.A.17.1.1	MIT	PMF? (uptake)	B
Ni²⁺	2.A.52.1.1	NiCoT	Uniport? (uptake)	B
Zn²⁺	2.A.4.1.1–2	CDF	PMF? (efflux)	B
Zn²⁺	2.A.4.2.1–2	CDF	PMF? (uptake)	Mito
Zn²⁺	2.A.4.2.3	CDF	PMF? (efflux)	An
Zn²⁺	2.A.4.3.1	CDF	PMF? (uptake)	An vesicles
Zn²⁺	2.A.5.1.1	ZIP	PMF? (uptake)	Y, Pl, An
Zn²⁺	2.A.6.1.2	RND	H⁺ antiport	B
I.D. Inorganic anions
Antimonite	2.A.45.1.1	ArsB	PMF (efflux)	B
Arsenite	2.A.45.1.1	ArsB	PMF (efflux)	B
Arsenite	2.A.59.1.1	ACR3	PMF (efflux)	Y
Bicarbonate	2.A.31.1.1	AE	Anion antiport	An, Y
Bicarbonate	2.A.31.2.1	AE	Na⁺ symport	An
Bicarbonate	2.A.73.1.1	ICT	H⁺ symporter?	B
Chlorate	2.A.17.3.1, -3	POT	H⁺ symport	Pl
Chloride	2.A.30.1–3	CCC	Na⁺:K⁺ symport	An
Chloride	2.A.30.4.1	CCC	Na⁺ symport	An
Chloride	2.A.30.5–6	CCC	K⁺ symport	An
Chloride	2.A.30.7.1	CCC	Na⁺:K⁺ symport	Pl
Chloride	2.A.31.1.1	AE	Anion antiport	An, Y
Chromate	2.A.51.1.1	CHR	PMF (efflux)	B
Cyanate	2.A.1.17.1	MFS	H⁺ symport	B
Inorganic anions (general)	2.A.31.1.1	AE	Anion antiport	An, Y, F, Pl
Inorganic monovalent anions (nonselective)	2.A.21.5.1	SSS	Na⁺ symport	An
Iodide	2.A.21.5.1	SSS	Na⁺ symport	An
Nitrate	2.A.1.8.2–6	MFS	H⁺ symport	B
Nitrate	2.A.17.3.1, 3	POT	H⁺ symport	Pl
Nitrite	2.A.1.8.1	MFS	Uniport; H⁺ antiport?	B
Nitrite	2.A.44.3.1	FNT	H⁺ symport?	B
Phosphate	2.A.1.4.1–4	MFS	H⁺ symport?; anion:anion antiport	B
Phosphate	2.A.1.9.1–3	MFS	H⁺ symport	Y, F, Pl
Phosphate	2.A.1.14.6	MFS	Na⁺ symport	An
Phosphate	2.A.20.1–3	Pit	H⁺ or Na⁺ symport	B, A, F
Phosphate	2.A.29.4.1	MC	OH⁻ antiport	Mito
Phosphate	2.A.47.2.1	DASS	H⁺ symport	Y
Phosphate	2.A.58.1.1	PNaS	Na⁺ symport	B, An
Silicate	2.A.32.1.1	Sit	Na⁺ symport	Diatoms
Sulfate	2.A.29.15.1	MC	SS antiport	Y (mito)
Sulfate	2.A.47.1.2	DASS	Na⁺ symport	An
Sulfate	2.A.53.1–4	SulP	H⁺ symport or HCO₃⁻ antiport	B, Y, F, Pl, An
Sulfate	2.A.51.1.2	CHR	H⁺ symport?	B
Thiosulfate	2.A.29.15.1	MC	SS antiport	Y (mito)
Tellurite	2.A.16.1.1	TDT	PMF (efflux)	B
II.A. Sugars and polyols
Arabinitol	2.A.1.18.1	MFS	H⁺ symport	B
Arabinose	2.A.1.1.2	MFS	H⁺ symport	B
Arabinose	2.A.1.2.14–15	MFS	H⁺ antiport	B
Fructose	2.A.1.1.13	MFS	H⁺ symport	An
Fructose	2.A.1.1.16	MFS	Uniport	Pr
l-Fucose	2.A.1.7.1	MFS	H⁺ symport	B
Galactose	2.A.21.3.1–2	SSS	Na⁺ symport	B, An
Galactose	2.A.1.1.1	MFS	H⁺ symport	B
Galactose	2.A.1.1.2	MFS	H⁺ symport	B
Galactose	2.A.1.1.6	MFS	Uniport	Y
Galactose	2.A.1.1.9	MFS	H⁺ symport	Y
Galactose	2.A.1.7.2	MFS	H⁺ symport	B
Glucose	2.A.1.1.4	MFS	Uniport	Y
Glucose	2.A.1.1.6	MFS	Uniport	Y
Glucose	2.A.1.1.12	MFS	Uniport	An
Glucose	2.A.1.1.16	MFS	Uniport	Pr
Glucose	2.A.1.1.17	MFS	?	Pr
Glucose	2.A.1.7.2	MFS	H⁺ symport	B
Glucose	2.A.1.7.3	MFS	H⁺ symport	B
Glucose	2.A.9.2.1	RhaT	H⁺ symport	B
Glucose	2.A.21.3.1	SSS	Na⁺ symport	An
Glucose	2.A.21.3.1–4	SSS	Na⁺ symport	B, An
Glucose (sensor)	2.A.1.1.18–19	MFS	?	Y
α-Glucosides	2.A.1.1.11	MFS	H⁺ symport	Y
Glucuronide	2.A.2.3.1	GPH	H⁺ symport	B
Hexoses	2.A.1.1.5	MFS	Uniport	Y, An
Hexoses	2.A.1.1.14	MFS	H⁺ symport	Pl
Hexoses	2.A.1.1.16	MFS	Uniport	Pr
Hexuronates	2.A.1.14.2	MFS	H⁺ symport	B
Isoprimeverose	2.A.2.3.3	GPH	H⁺ symport	B
Isopropyl-β-thiogalactoside (efflux)	2.A.1.20.1, -4	MFS	H⁺ antiport	B
Isopropyl-β-thiogalactoside (efflux)	2.A.1.2.15, -18	MFS	H⁺ antiport	B
Lactose	2.A.1.1.9	MFS	H⁺ symport	Y
Lactose (efflux)	2.A.1.20.1, -2 and 4	MFS	H⁺ antiport	B
Lactose	2.A.1.5.1	MFS	H⁺ symport	B
Lactose	2.A.2.2.1	GPH	H⁺ symport	B
Maltose	2.A.1.1.10	MFS	H⁺ symport	Y
Maltose (efflux)	2.A.1.20.1	MFS	H⁺ antiport	B
Mannose	2.A.1.1.16	MFS	Uniport	Pr
Mannose	2.A.1.7.3	MFS	H⁺ symport	B
Melibiose	2.A.1.5.4	MFS	H⁺ symport	B
Melibiose (efflux)	2.A.1.2.18	MFS	H⁺ antiport	B
Melibiose	2.A.2.1.1	GPH	H⁺ or Na⁺ symport	B
Multiple sugars	2.A.1.20	MFS	H⁺ antiport
Myoinositol	2.A.1.1.8	MFS	H⁺ symport	Y
Myoinositol	2.A.1.1.20	MFS	H⁺ symport	Pr
Myoinositol	2.A.21.4.1	SSS	Na⁺ symport	An
Pentosides	2.A.2.3.2–3	GPH	H⁺ symport	B
Raffinose	2.A.1.5.2	MFS	H⁺ symport	B
Raffinose	2.A.2.2.2	GPH	H⁺ symport	B
l-Rhamnose	2.A.9.1.1	RhaT	H⁺ symport	B
Ribitol	2.A.1.18.2	MFS	H⁺ symport	B
Ribose	2.A.9.3.1	RhaT	H⁺ symport	B
Sialic acid	2.A.1.12.1	MFS	H⁺ symport	B
Sucrose	2.A.1.5.3	MFS	H⁺ symport	B
Sucrose	2.A.2.4.1	GPH	H⁺ symport	Pl
Sugars (efflux) (fairly nonspecific)	2.A.1.20.1, -2, -4	MFS	H⁺ antiport	B
Xylose	2.A.1.1.2	MFS	H⁺ symport	B
Xylose	2.A.1.1.3	MFS	H⁺ symport	B
II.B. Monocarboxylates
Acetate	2.A.44.4.1	FNT	H⁺ symport	Y
Allantoate	2.A.1.14.4	MFS	H⁺ symport	Y
Auxin (indole 3-acetate)	2.A.18.1.1	AAAP	H⁺ symport	Pl
Auxin (out)	2.A.69.1.1	AEC	Uniport? H⁺ antiport?	Pl
Benzoate	2.A.1.15.5	MFS	H⁺ symport	B
Benzoate	2.A.46.1.1	BenE	H⁺ symport	B
Bile salts	2.A.1.3.13	MFS	H⁺ symport	B
Bile salts	2.A.6.2.5	RND	H⁺ antiport	B
Bile salts	2.A.28.1.1	BASS	Na⁺ symport	An
Bile salts (conjugated)	2.A.1.23.1	MFS	H⁺ symport	B
Bile salts (conjugated and unconjugated)	2.A.60.1	OAT	?	An
Bilirubin	2.A.65.1.1	BRT	H⁺ symport?	An
Cyanate	2.A.1.17.1	MFS	H⁺ symport	B
2,4-Dichlorophenoxy acetate	2.A.1.15.3	MFS	H⁺ symport	B
Digoxin	2.A.60.1.1	OAT	Uniport; anion antiport	An
Fatty acids	2.A.6.2.5	RND	H⁺ antiport	B
Formate	2.A.1.11.1	MFS	SS antiport	B
Formate	2.A.44.1.1	FNT	Efflux?	B
Formate	2.A.44.2.1	FNT	Uptake?	B
Galacturonate	2.A.1.14.2	MFS	H⁺ symport	B
Glucarate	2.A.1.14.1	MFS	H⁺ symport	B
Gluconate	2.A.8.1.1	GntP	H⁺ symport	B
Gluconate	2.A.8.1.2	GntP	H⁺ symport	B
Glucuronate	2.A.1.14.2	MFS	H⁺ symport	B
Hexuronate	2.A.1.14.2	MFS	H⁺ symport	B
4-Hydroxybenzoate	2.A.1.15.1	MFS	H⁺ symport	B
3-Hydroxyphenyl acetate	2.A.1.14.9	MFS	H⁺ symport	B
3-Hydroxyphenyl propionate	2.A.1.15.2	MFS	H⁺ symport	B
l-Idonate	2.A.8.1.2	GntP	H⁺ symport	B
2-Keto-3-deoxygluconate	2.A.10.1.1	KDGT	H⁺ symport	B
Lactate	2.A.1.12.2	MFS	H⁺ symport	Y
Lactate	2.A.1.13.1	MFS	H⁺ symport	Y, F, An
Lactate	2.A.14.1.1	LctP	H⁺ symport	B
Lactate	2.A.24.3.2	CCS	SS antiport	B
Leucotrienes	2.A.60.1.7	OAT	?	An
4-Methyl-o-phthalate	2.A.1.6.5	MFS	H⁺ symport	B
Mevalonate	2.A.1.13.1	MFS	H⁺ symport	Y, F, An
Monocarboxylates	2.A.1.13.1	MFS	H⁺ symport	Y, F, An
Organic anions (nonselective)	2.A.1.19.4, -7, -8	MFS	H⁺ symport?	An
cis,cis-Muconate	2.A.1.15.4	MFS	H⁺ symport	B
Organic anions (nonselective)	2.A.1.19.4, -7, -8	MFS	H⁺ symport?	An
Organic anions (nonselective)	2.A.21.5.2	SSS	Na⁺ symport	An
Organic anions (nonselective)	2.A.60.1	OAT	Uniport; anion antiport	An
Organic anions (nonselective)	2.A.65.1.1	BRT	H⁺ symport?	An
Phenylpropionate	2.A.1.27.1	MFS	H⁺ symport	B
Phenylacetate	2.A.21.7.1	SSS	H⁺ symport	B
Phthalate	2.A.1.14.5	MFS	H⁺ symport	B
Prostaglandins	2.A.60.1.2, -7	OAT	Uniport; anion antiport	An
Protocatechuate	2.A.1.15.1	MFS	H⁺ symport	B
Pyruvate	2.A.1.12.1	MFS	H⁺ symport	Y
Pyruvate	2.A.1.13.1	MFS	H⁺ symport	Y, F, An
Quinate	2.A.1.1.7	MFS	H⁺ symport	F
Shikimate	2.A.1.6.6	MFS	H⁺ symport	B
Sialate	2.A.1.12.1	MFS	H⁺ symport	B
Tartrate	2.A.1.14.3	MFS	H⁺ symport	B
Tartrate	2.A.47.3.3	DASS	SS antiport	B
Taurocholate	2.A.60.1.3, -7	OAT	?	An
Thromboxanes	2.A.60.1.2, -7	OAT	?	An
Thyroid hormones (thyroxin; triiodothyronine)	2.A.60.1.3	OAT	?	An
II.C. Di- and tricarboxylates
Citrate	2.A.1.6.1	MFS	H⁺ symport	B
Citrate	2.A.11.1.1	CitMHS	Mg²⁺:H⁺ symport	B
Citrate	2.A.11.1.2	CitMHS	H⁺ symport	B
Citrate	2.A.24.1.1; 3.1, 3.2	CCS	Na⁺ symport	B
Citrate	2.A.47.1.3, 3.2	DASS	Na⁺ symport; SS antiport	B, An
Dicarboxylates	2.A.1.6.3	MFS	H⁺ symport	B
Dicarboxylates	2.A.13.1.1–2	Dcu	SS antiport	B
Dicarboxylates	2.A.16.2.1	TDT	H⁺ symport	Y
Dicarboxylates	2.A.23.1.3	DAACS	H⁺ symport	B
Dicarboxylates	2.A.29.2.1–2; 13.1	MC	SS antiport	Mito
Dicarboxylates	2.A.47.1.1, -3	DASS	Na⁺ symport	An
Dicarboxylates	2.A.47.3.1–3	DASS	SS antiport	B, chloro
Dicarboxylates	2.A.56.1.1	TRAP-T	H⁺ symport	B
Dicarboxylates	2.A.61.1.1	DcuC	H⁺ symport	B
α-Ketoglutarate	2.A.1.6.2	MFS	H⁺ symport	B
Malate	2.A.16.2.1	TDT	H⁺ symport?	Y
Malate	2.A.24.2.1	CCS	H⁺ symport	B
Malate	2.A.69.3.1	AEC	H⁺ symport?	B
Malonate	2.A.29.15.1	MC	SS antiport	Y (mito)
Malonate	2.A.69.2.1	AEC	H⁺ symport?	B
Malonate	2.A.70.2.1	MSS	H⁺ symport?	B
Malonate	2.A.70.1.1	MSS	Na⁺ symport	B
Oxalate	2.A.1.11.1	MFS	SS antiport	B
Oxaloacetate	2.A.29.15.1	MC	SS antiport	Y (mito)
Tricarboxylates	2.A.29.7.1	MC	SS antiport	Mito
Tricarboxylates	2.A.54.1.1	MTC	H⁺ symport	Mito
II.D. Organic anions (noncarboxylates)
Glucose-phosphate	2.A.1.4.1	MFS	P_i antiport	B
Glucose 6-phosphate (sensor)	2.A.1.4.4	MFS	?	B
Glucose 6-phosphate	2.A.1.4.5	MFS	P_i antiport	An
Glucose 6-phosphate	2.A.50.2.1	TP-NST	P_i antiport	Plastids (Pl)
Phosphoglycerates	2.A.1.4.2	MFS	P_i antiport	B
Glycerolphosphate	2.A.1.4.3	MFS	P_i antiport	B
Hexosephosphates	2.A.1.4.1	MFS	P_i antiport	B
Phosphoenolpyruvate	2.A.1.4.2	MFS	P_i antiport	B
Phosphoenolpyruvate	2.A.50.3.1	TP-NST	P_i antiport	Chloro (Pl)
Sugar-phosphates	2.A.1.4.1	MFS	P_i antiport	B
Triosephosphate	2.A.50.1.1	TP-NST	P_i antiport	Chloro (Pl)
Triosephosphate	2.A.50.2.1	TP-NST	P_i antiport	Plastids (Pl)
III.A. Amino acids and conjugates
Acidic amino acids	2.A.3.10.13	APC	H⁺ symport	Y
Alanine	2.A.3.1.7	APC	H⁺ symport	B
Alanine	2.A.25.1.1	AGCS	Na⁺ symport	B
Alanine	2.A.25.1.2	AGCS	Na⁺ or H⁺ symport	B
β-Alanine	2.A.3.1.5	APC	H⁺ symport	B
γ-Aminobutyrate	2.A.3.1.4	APC	H⁺ symport	B
γ-Aminobutyrate	2.A.3.1.5	APC	H⁺ symport	B
γ-Aminobutyrate	2.A.3.7.1	APC	Glutamate antiport	B
γ-Aminobutyrate	2.A.18.5.1	AAAP	H⁺ symport?	An
γ-Aminobutyrate	2.A.22.3.1–2	NSS	Na⁺ symport	An
Arginine	2.A.3.10.4	APC	H⁺ symport	Y
Arginine	2.A.3.2.3	APC	Antiport with ornithine	B
Arginine	2.A.65.1.1	LysE	H⁺ antiport?	B
Aromatic amino acids	2.A.3.1.3	APC	H⁺ symport	B
Asparagine	2.A.3.1.8	APC	H⁺ symport	B
Asparagine	2.A.3.10.7, -13	APC	H⁺ symport	Y
Aspartate	2.A.13.1.1	Dcu	SS antiport	B
Aspartate	2.A.23.1.1	DAACS	H⁺ symport	B
Aspartate	2.A.23.1.2	DAACS	H⁺ or Na⁺ symport	B, An
Aspartate	2.A.23.2.1	DAACS	H⁺ or Na⁺ symport	B, An
Basic amino acids	2.A.3.1.19	APC	H⁺ symport	Y
Basic amino acids	2.A.3.3.1, -2	APC	H⁺ symport	An
Basic amino acids	2.A.3.8.3	APC	Uniport or H⁺ symport	An
Basic amino acids	2.A.29.9.1	MC	SS antiport	Mito
Branched-chain amino acids	2.A.3.10.11	APC	H⁺ symport	Y
Branched-chain amino acids	2.A.26.1.1–3	LIVCS	H⁺ or Na⁺ symport	B
Cystine	2.A.3.8.5	APC	Glutamate antiport	An
Cystine	2.A.43.1.1	LCT	H⁺ antiport	An
General amino acids (all l, some d)	2.A.3.3.3	APC	H⁺ symport	Pl
General amino acids	2.A.3.10.2, -14	APC	H⁺ symport	Y
General amino acids	2.A.18.2.1	AAAP	H⁺ symport	Pl
Glutamate	2.A.3.7.1	APC	γ-Aminobutyrate antiport	B
Glutamate	2.A.3.8.5	APC	Cystine antiport	An
Glutamate	2.A.3.10.13	APC	H⁺ symport	Y
Glutamate	2.A.23.1.1	DAACS	H⁺ symport	B
Glutamate	2.A.23.1.2	DAACS	H⁺ or Na⁺ symport	B, An
Glutamate	2.A.23.2.1	DAACS	H⁺ or Na⁺ symport	B, An
Glutamate	2.A.23.2.2	DAACS	Na⁺ symport	An
Glutamate	2.A.27.1.1	ESS	Na⁺ symport	B
Glutamine	2.A.3.7.1	APC	H⁺ symport	B
Glutamine	2.A.3.10.5, -7	APC	H⁺ symport	Y
Glycine	2.A.3.1.7	APC	H⁺ symport	B
Glycine	2.A.22.2.2	NSS	Na⁺ symport	An
Glycine	2.A.25.1.1	AGCS	Na⁺ symport	B
Histidine	2.A.3.1.5, -9	APC	H⁺ symport	Y, F
Histidine	2.A.3.10.1	APC	H⁺ symport	Y
Histidine	2.A.17.3.2–3	POT	H⁺ symport	Pl
Homoserine (efflux)	2.A.76.1.1	RhtB	H⁺ antiport	B
Homoserine lactone (efflux)	2.A.76.1.1	RhtB	H⁺ antiport	B
Isoleucine	2.A.3.10.6	APC	H⁺ symport	Y
Isoleucine	2.A.26.1.1–3	LIVCS	H⁺ or Na⁺ symport	B
Leucine	2.A.3.10.6	APC	H⁺ symport	Y
Leucine (sensor)	2.A.3.10.12	APC	?	Y
Leucine	2.A.26.1.1–3	LIVCS	H⁺ or Na⁺ symport	B
Lysine	2.A.3.1.2	APC	H⁺ symport	B
Lysine	2.A.3.2.2	APC	SS antiport	B
Lysine	2.A.3.2.4	APC	?	B
Lysine	2.A.3.10.10	APC	H⁺ symport	Y
Lysine (efflux)	2.A.75.1.1	LysE	H⁺ antiport?	B
Methionine	2.A.3.8.4	APC	H⁺ symport	Y
Neutral amino acids	2.A.3.8.1–3, -6	APC	Uniport or H⁺ symport	An
Neutral amino acids	2.A.18.4.1	AAAP	H⁺ symport	F
Neutral amino acids	2.A.23.3.1	DAACS	Na⁺ symport	An
Neutral and acidic amino acids	2.A.23.3.2	DAACS	Na⁺ symport	An
Neutral and basic amino acids	2.A.23.3.3	DAACS	Na⁺ symport	An
Ornithine	2.A.3.2.1	APC	Antiport with putrescine	B
Ornithine	2.A.3.2.3	APC	Antiport with arginine	B
Phenylalanine	2.A.3.1.1	APC	H⁺ symport	B
Proline	2.A.1.6.4	MFS	H⁺ symport	B
Proline	2.A.3.1.6	APC	H⁺ symport	Y
Proline	2.A.3.10.3	APC	H⁺ symport	Y
Proline	2.A.15.1.2	BCCT	H⁺ symport	B
Proline	2.A.18.3.1	AAAP	H⁺ symport	Pl
Proline	2.A.21.2.1	SSS	Na⁺ symport	B
Proline	2.A.22.2.1	NSS	Na⁺ symport	An
Serine	2.A.3.1.7	APC	H⁺ symport	B
Serine	2.A.23.4.1	DAACS	Na⁺ symport	B
Serine	2.A.42.2.1	HAAAP	H⁺ symport	B
Threonine	2.A.3.1.9	APC	H⁺ symport	B
Threonine	2.A.23.4.1	DAACS	Na⁺ symport	B
Threonine	2.A.42.2.2	HAAAP	H⁺ symport	B
Threonine (efflux)	2.A.76.1.2	RhtB	H⁺ antiport?	B
Tryptophan	2.A.3.1.16–17	APC	H⁺ symport	Y
Tryptophan	2.A.22.4.1	SSS	Na⁺ symport	B
Tryptophan	2.A.42.1.2–3	HAAAP	H⁺ symport	B
Tyrosine	2.A.3.10.8, -9	APC	H⁺ symport	Y
Tyrosine	2.A.42.1.1	HAAAP	H⁺ symport	B
Tyrosine	2.A.45.2.1	ArsB	?	An
Valine	2.A.3.10.6, -9	APC	H⁺ symport	Y
Valine	2.A.26.1.1–3	LIVCS	H⁺ or Na⁺ symport	B
III.B. Amines, amides, and polyamines
Acetylcholine	2.A.1.2.13	MFS	H⁺ antiport	An
Acylcarnitine	2.A.1.19.3	MFS	Uniport; Na⁺ symport	An
S-Adenosylmethionine	2.A.3.10.15	APC	H⁺ symport	Y
Acylcarnitine	2.A.29.8.1	MC	SS antiport	Mito
Amines, organic (nonspecific)	2.A.1.19.1–5	MFS	Uniport?	An
γ-Aminobutyrate	2.A.3.4.2	APC	H⁺ symport	F, Y
γ-Aminobutyrate	2.A.3.7.1	APC	H⁺ symport	B
Auxin	2.A.18.1.1	AAAP	H⁺ symport	Pl
Auxin	2.A.69.1.1–2	AEC	Uniport; H⁺ antiport?	Pl
Betaine	2.A.1.6.4	MFS	H⁺/Na⁺ symport	B
Betaine	2.A.23.3.1	SSS	Na⁺ symport	An
Butyrobetaine	2.A.1.19.3	MFS	Uniport; Na⁺ symport	An
Cadaverine	2.A.3.2.2	APC	Antiport with lysine	B
Carnitine	2.A.1.19.3	MFS	Uniport; Na⁺ symport	An
Carnitine	2.A.15.2.1	BCCT	H⁺ symport	B
Carnitine	2.A.29.8.1	MC	SS antiport	Mito
Choline	2.A.3.4.1	APC	H⁺ symport?	Y
Choline	2.A.15.3.1	BCCT	H⁺ symport	B
Choline	2.A.22.3.5	NSS	Na⁺ symport	An
Creatine	2.A.22.3.4	NSS	Na⁺ symport	An
Dopamine	2.A.1.22.1	MFS	?	An
Dopamine	2.A.22.1.3	NSS	Na⁺ symport	An
Ectosine	2.A.15.1.2	BCCT	H⁺ symport	B
Ethanolamine	2.A.3.5.1	APC	H⁺ symport	B
Glycine betaine	2.A.1.6.4	MFS	H⁺/Na⁺ symport	B
Glycine betaine	2.A.1.19.3	MFS	Uniport; Na⁺ symport	An
Glycine betaine	2.A.15.1.1–2	BCCT	H⁺ symport	B
Glycine betaine	2.A.22.3.1	NSS	Na⁺ symport	An
Guanidinium	2.A.1.19.2	MFS	H⁺ antiport	An
Monoamines	2.A.1.2.11	MFS	H⁺ antiport	An
Monoamines	2.A.1.2.12	MFS	H⁺ antiport	An
Neurotransmitters (cationic)	2.A.1.19.1	MFS	Uniport?	An
Neurotransmitters (cationic)	2.A.1.19.5–7	MFS	Uniport?	An
Neurotransmitters (cationic)	2.A.1.22.1	MFS	Uniport or H⁺ or Na⁺ symport	An
Noradrenaline	2.A.22.1.2	NSS	Na⁺ symport	An
Organocations	2.A.1.19.1–5	MFS	Uniport or H⁺ or Na⁺ symport	An
Polyamines (efflux)	2.A.1.2.16	MFS	H⁺ antiport	An
Putrescine	2.A.3.2.1	APC	H⁺ symport; antiport with ornithine	B
Quaternary amines	2.A.77.1.2	CadD	H⁺ antiport?	B
Serotonin	2.A.22.1.1	NSS	Na⁺ symport	An
Taurine	2.A.22.3.3	NSS	Na⁺ symport	An
Tetramethyl ammonium	2.A.1.19.1	MFS	H⁺ antiport; uniport?	An
Urea	2.A.21.6.1	SSS	?	Y
III.C. Peptides
Glycopeptides, cell wall derived	2.A.1.25.2	MFS	H⁺ symport?	B
Peptides	2.A.17.1–4	POT	H⁺ symport	B, Y, Pl, An
Peptides	2.A.67.1–2	OPT	H⁺ symport?	B, A, Y, Pl
Peptides	9.A.18	PUP	?	B
Peptides, antibacterial (efflux)	2.A.6.2.5	RND	H⁺ antiport	B
Peptides, cell wall derived	2.A.1.25.2	MFS	H⁺ symport?	B
IV.A. Nucleobases
Allantoin	2.A.39.3.1	NCS1	H⁺ symport	Y
Cytosine	2.A.39.1.1	NCS1	H⁺ symport	B
Cytosine	2.A.39.2.1	NCS1	H⁺ symport	Y
Nucleobases	2.A.74.1.1	MET	H⁺ antiport?	An
Purines	2.A.39.2.1	NCS1	H⁺ symport	Y
Purines	2.A.40.2.1	NCS2	H⁺ symport	B
Purines	2.A.40.5.1	NCS2	H⁺ symport	F
Uracil	2.A.39.3.2	NCS1	H⁺ symport	Y
Uracil	2.A.40.1.1	NCS2	H⁺ symport	B
Uric acid	2.A.40.4.1	NCS2	H⁺ symport	F
Xanthine	2.A.40.3.1	NCS2	H⁺ symport	B
Xanthine	2.A.40.4.1	NCS2	H⁺ symport	F
IV.B. Nucleosides
Nucleosides	2.A.1.10.1	MFS	H⁺ symport	B
Nucleosides	2.A.21.3.3	SSS	Na⁺ symport	An
Nucleosides	2.A.41.1.1	CNT	H⁺ symport	B
Nucleosides	2.A.41.2.2–5	CNT	Na⁺ symport	An
Nucleosides (pyrimidine specific)	2.A.41.1.2	CNT	Na⁺ symport	B
Nucleosides (purine specific)	2.A.41.2.1	CNT	Na⁺ symport	An
Nucleosides	2.A.57.1–3	ENT	Uniport	Y, Pr, An
Nucleosides	2.A.74.1.1	MET	H⁺ antiport?	An
Nucleosides	9.A.6.1.1	INT	?	An
Uridine	2.A.39.3.2–3	NCS1	H⁺ symport	Y
Xanthosine	2.A.1.10.2	MFS	H⁺ symport	B
IV.C. Nucleotides
ADP	2.A.12.1.1, -2	AAA	SS antiport	B
ADP	2.A.12.2.1	AAA	SS antiport	Pl
ADP	2.A.29.1.1	MC	SS antiport	Mito
ATP	2.A.12.1.1	AAA	SS antiport	B
ATP	2.A.12.1.2	AAA	SS antiport	Pl
ATP	2.A.29.1.1	MC	SS antiport	Mito
Nucleoside triphosphates	2.A.12.3.1	AAA	H⁺ symport	B
V.A. Vitamins/cofactor precursors
l-Ascorbate	2.A.40.6.1	NCS2	Na⁺ symport	An
p-Aminobenzoylglutamate	2.A.68.1.1	AbgT	H⁺ symport	B
Anionic vitamins	2.A.21.5.2	SSS	Na⁺ symport	An
Biopterin	2.A.71.1.1–4	FBT	H⁺ symport?	Pr
Biotin	2.A.21.5.2	SSS	Na⁺ symport	An
Cationic vitamins	2.A.1.19.1	MFS	Uniport	An
Flavin adenine dinucleotide	2.A.29.10.1	MC	?	Mito
Folate (reduced)	2.A.48.1.1	RFC	H⁺ symport	An
Folate	2.A.71.1.1–4	FBT	H⁺ symport?	Pr
5-Formyltetrahydrofolate	2.A.48.1.1	RFC	Na⁺ symport?	An
Lipoate	2.A.21.5.2	SSS	Na⁺ symport	An
Nicotinate	2.A.65.1.1	BRT	H⁺ symport	An
Pantothenate	2.A.21.1.1	SSS	Na⁺ symport	B
Pantothenate	2.A.21.5.2	SSS	Na⁺ symport	An
Tetrahydrofolate	2.A.48.1.1	RFC	Na⁺ symport?	An
Thiamine	2.A.39.4.1	NCS1	H⁺ symport	Y
Thiamine	2.A.48.2.1	RFC	Na⁺ symport?	An
V.B. Enzyme and redox cofactors
Acetyl coenzyme A	2.A.1.25.1	MFS	SS antiport	An (ER)
S-Adenosylmethionine	2.A.3.10.15	APC	H⁺ symport?	Y
CMP-sialate	2.A.50.7.1	TP-NST	CMP antiport	An (ER)
Coenzyme A	2.A.1.25.1	MFS	SS antiport	An (ER)
Flavin adenine dinucleotide	2.A.29.10.1	MC	?	Mito
GDP-mannose	2.A.50.8.1	TP-NST	GMP antiport	An, Y (ER)
Nicotinamide mononucleotide	9.A.4.1.1	PnuC	?	B
UDP-N-acetylglucosamine	2.A.50.5.1	TP-NST	UMP antiport	Y, An (ER)
UDP-galactose	2.A.50.6.1	TP-NST	UMP antiport	An (ER)
V.C. Siderophores and Fe-siderophore complexes
Fe-enterobactin	2.A.1.16.2	MFS	H⁺ symport?	Y
Fe-ferrioxamine	2.A.1.16.1	MFS	H⁺ symport?	Y
Fe-siderophore	2.A.1.16.1	MFS	H⁺ symport?	Y
Fe-triacetylfusarinine	2.A.1.16.3	MFS	H⁺ symport?	Y
V.D. Signaling molecules
Acyl l-homoserine lactone	2.A.6.2.6	RND	H⁺ antiport	B
Isoflavenoids	2.A.6.2.3	RND	H⁺ antiport	B
Nodulation factor	2.A.6.3.1	RND	H⁺ antiport	B
Prostaglandins	2.A.60.1.2	OAT		An
Steroid hormones	2.A.1.19.4	MFS		An
Steroid hormones	2.A.6.6	RND		An, Y
Thyroid hormones (thyroxine, triiodothyronine)	2.A.60.1.3, -7	OAT		An
VI.A. Multiple drugs and dyes
Multiple drugs	2.A.1.2.5	MFS	H⁺ antiport	B
Multiple drugs	2.A.1.2.6	MFS	H⁺ antiport	Y
Multiple drugs	2.A.1.2.7	MFS	H⁺ antiport	B
Multiple drugs	2.A.1.2.8	MFS	H⁺ antiport	B
Multiple drugs	2.A.1.2.9	MFS	H⁺ antiport	B
Multiple drugs	2.A.1.2.10	MFS	H⁺ antiport	B
Multiple drugs	2.A.1.2.11–12	MFS	H⁺ antiport	An
Multiple drugs	2.A.1.2.16, -17	MFS	H⁺ antiport	An
Multiple drugs	2.A.1.3.1	MFS	H⁺ antiport	Y
Multiple drugs	2.A.1.3.2	MFS	H⁺ antiport	B
Multiple drugs	2.A.1.3.3	MFS	H⁺ antiport	B
Multiple drugs	2.A.1.3.4	MFS	H⁺ antiport	B
Multiple drugs	2.A.1.3.5	MFS	H⁺ antiport	B
Multiple drugs (cationic)	2.A.1.19.1	MFS	Uniport	An
Multiple drugs (aminoglycosides)	2.A.1.20.1	MFS	H⁺ antiport?	B
Multiple drugs	2.A.1.21.1–4	MFS	H⁺ antiport	B
Multiple drugs	2.A.6.2.1–2, -6	RND	H⁺ antiport	B
Multiple drugs and dyes (cationic)	2.A.7.1.1–2	SMR	H⁺ antiport	B
Multiple drugs (antibiotics) (uptake)	2.A.17.4.1	POT	H⁺ symport	An
Multiple drugs (antibiotics) (uptake)	2.A.1.25.2	MFS	H⁺ symport	B
Multiple drugs (antibiotics)	2.A.66.1–3	MATE	H⁺ antiport	B, Y
Multiple drugs (antibiotics)	2.A.74.1.1–2	MET	H⁺ antiport?	An
Xenobiotics	2.A.1.19.1	MFS	Uniport	An
VI.B. Specific drugs
Acriflavin	2.A.1.2.8	MFS	H⁺ antiport	B
Acriflavin	2.A.1.3.3	MFS	H⁺ antiport	B
Actinorhordin	2.A.1.3.7	MFS	H⁺ antiport	B
Actinorhordin	2.A.6.5.1	RND	H⁺ antiport	B
Amiloride	2.A.1.2.1	MFS	H⁺ antiport	Y
Aminoglycosides	2.A.1.20.1	MFS	H⁺ antiport?	B
Aminotriazole	2.A.1.3.1	MFS	H⁺ antiport	Y
Ampicillin (in)	2.A.1.25.2	MFS	H⁺ symport?	B
Benomyl	2.A.1.2.6	MFS	H⁺ antiport	Y
Bicyclomycin	2.A.1.2.7	MFS	H⁺ antiport	B
Bile acids	2.A.1.3.13	MFS	H⁺ antiport	B
Bleomycin	2.A.1.21.2	MFS	H⁺ antiport	B
Carbonylcyanide m-chlorophenylhydrazone (CCCP)	2.A.1.2.9	MFS	H⁺ antiport	B
CCCP	2.A.1.3.2	MFS	H⁺ antiport	B
Cephamycin	2.A.1.3.8	MFS	H⁺ antiport	B
Chloramphenicol	2.A.1.2.3	MFS	H⁺ antiport	B
Chloramphenicol	2.A.1.2.8	MFS	H⁺ antiport	B
Cycloheximide	2.A.1.2.2	MFS	H⁺ antiport	Y
Cycloheximide	2.A.1.2.6	MFS	H⁺ antiport	Y
Daunomycin	2.A.1.2.5	MFS	H⁺ antiport	B
Dauxorubicin	2.A.1.2.11	MFS	H⁺ antiport	An
Erythromycin	2.A.1.21.1	MFS	H⁺ antiport	B
Ethidium bromide	2.A.1.2.5	MFS	H⁺ antiport	B
Ethidium bromide	2.A.1.2.8	MFS	H⁺ antiport	B
Ethidium bromide	2.A.1.2.11	MFS	H⁺ antiport	An
Ethidium bromide	2.A.1.3.3	MFS	H⁺ antiport	B
Ethidium bromide	2.A.66.1.1	MATE	H⁺ antiport	B
Ethionine	2.A.66.3.1	MATE	H⁺ antiport	Y
Fluconazole	2.A.1.2.17	MFS	H⁺ antiport	Y
Fluoroquinolones	2.A.1.2.8	MFS	H⁺ antiport	B
Fluoroquinolones	2.A.1.3.3	MFS	H⁺ antiport	B
Hydrophobic uncouplers	2.A.1.2.9	MFS	H⁺ antiport	B
Isoflavinoid	2.A.6.2.3	RND	H⁺ antiport	B
Kanamycin	2.A.1.20.1	MFS	H⁺ antiport?	B
Kanamycin	2.A.66.1.1	MATE	H⁺ antiport	B
β-Lactams (uptake)	2.A.17.4.1	POT	H⁺ symport	An
Lincomycin	2.A.1.3.9	MFS	H⁺ antiport	B
Macrolides	2.A.1.21.1	MFS	H⁺ antiport	B
Methotrexate	2.A.1.2.6	MFS	H⁺ antiport	Y
Methotrexate	2.A.48.1.1	RFC	Na⁺ symport?	An
Methotrexate	2.A.60.1.4	OAT	?	An
Methylenomycin	2.A.1.3.10	MFS	H⁺ antiport	B
Methylviologen	2.A.1.3.14	MFS	H⁺ antiport	B
Nalidixic acid	2.A.1.3.2	MFS	H⁺ antiport	B
Nitroquinoline-N-oxide	2.A.1.3.1	MFS	H⁺ antiport	Y
Norfloxacin	2.A.66.1.1	MATE	H⁺ antiport	B
Oleandomycin	2.A.1.21.1	MFS	H⁺ antiport	B
Organocations	2.A.1.3.4	MFS	H⁺ antiport	B
Organomercurials	2.A.1.3.2	MFS	H⁺ antiport	B
Paraquat	2.A.1.2.16	MFS	H⁺ antiport	Y
Penicillin and derivatives (in)	2.A.1.25.2	MFS	H⁺ symport	B
Pristinamycin	2.A.1.3.5	MFS	H⁺ antiport	B
Puromycin	2.A.1.3.11	MFS	H⁺ antiport	B
Puromycin	2.A.1.21.2	MFS	H⁺ antiport	B
Quinoline	2.A.1.2.10	MFS	H⁺ antiport	B
Rifamycin	2.A.1.3.5	MFS	H⁺ antiport	B
Rifamycin	2.A.1.3.15	MFS	H⁺ antiport	B
Streptomycin	2.A.1.20.1	MFS	H⁺ antiport?	B
Streptomycin	2.A.66.1.1	MATE	H⁺ antiport	B
Sulfathiazole	2.A.1.27	MFS	H⁺ antiport	B
Tetracenomycin	2.A.1.3.12	MFS	H⁺ antiport	B
Tetracycline	2.A.1.2.4	MFS	H⁺ antiport	B
Tetracycline	2.A.1.3.6	MFS	H⁺ antiport	B
Tetracycline	2.A.1.21.2–3	MFS	H⁺ antiport	B
VI.C. Bile salts and conjugates
Bile salts	2.A.1.19.4	MFS	Uniport or H⁺ symport	An
Bile salts	2.A.6.2.5	RND	H⁺ antiport	B
Bile salts	2.A.28.1.1	BASS	Na⁺ symport	An
Bile salt conjugates	2.A.1.23.1	MFS	H⁺ symport	B
Organic solvents	2.A.6.2.4	RND	H⁺ antiport	B
Toluene	2.A.6.2.4	RND	H⁺ antiport	B
VI.D. Sterols/steroids
Steroids	2.A.6.2.5	RND	H⁺ antiport	B
Sterols (nonspecific)	2.A.1.19.4	MFS	Uniport; H⁺ symport	An
Sterols (nonspecific; probable)	2.A.6.6.1, -3	RND	H⁺ antiport?	Y, An
Sterols (nonspecific)	2.A.74.1.1	MET	H⁺ antiport?	An
Aldosterone	2.A.6.6.1, -3	RND	H⁺ antiport?	Y, An
Cardiac glycosides	2.A.6.6.1, -3	RND	H⁺ antiport?	Y, An
Cortisol	2.A.6.6.1, -3	RND	H⁺ antiport?	Y, An
Dexamethasone	2.A.6.6.1, -3	RND	H⁺ antiport?	Y, An
Estrone-3-sulfate	2.A.6.6.1, -3	RND	H⁺ antiport?	Y, An
Estradiol 17-glucuronide	2.A.6.6.1, -3	RND	H⁺ antiport?	Y, An
Ouabain	2.A.6.6.1, -3	RND	H⁺ antiport?	Y, An
Steroid conjugates	2.A.6.6.1, -3	RND	H⁺ antiport?	Y, An
Steroid hormones (conjugated and unconjugated)	2.A.60.1	OAT	?	An
VII.A. Carbohydrates
Lipooligosaccharides	2.A.6.3.1	RND	H⁺ antiport?	B
Exo- and capsular polysaccharides (out)	9.A.1.2.1–2	PST	H⁺ antiport?	B
Lipopolysaccharide (out)	9.A.1.1	PST	H⁺ antiport?	B
VII.B. Proteins
Proteins (nonspecific)	2.A.6.4.1	RND (SecDF)	H⁺ antiport?	B, A
Redox enzymes/proteins	2.A.64.1.1	TAT	PMF driven	B, A, E
VII.D. Lipids
Lipids	2.A.6.5.2	RND	PMF driven	B
Lipids	2.A.31.1.1	AE	?	An

Abbreviations are defined in Table 3, footnote d, and in Table 2. ER, endoplasmic reticulum; SS antiport, solute/solute antiport.