Table 2 Approximate number of components of the L-malate decarboxylation pathway (MleP and MleS), co-reconstituted solute transporters (GltP and LacY) and enzymes of the lactose metabolism pathway (β-galactosidase (LacZ), hexokinase (HK) and glucose-6-phosphate dehydrogenase (G6P-DH)) in vesicles composed of E. coli polar lipids:egg PC 3:1 (mol ratio)

Component	Molecular weight	Oligomeric unit	Internal concentration	Molecules per vesicle
Component	Molecular weight	Oligomeric unit	Internal concentration	100 nm	200 nm	400 nm
MleP	47.9 kDa	Dimerⁱ	LPR 250 (w/w)	6 (3)	25 (12)	100 (50)
MleS	62.1 kDa	Dimerⁱⁱ	2.5 µM	2	8	48
NAD⁺			1 mM	246	2230	19000
Mn²⁺			0.5 mM	125	1125	9500
L-lactate⁻			2 mM	500	4500	38000
Pyranine			0.1 mM	25	223	1900
GltP	48.8 kDaⁱⁱⁱ	Trimer^iv	LPR 250 (w/w)	6	25	100
LacY	46.5 kDa	Monomer^v	LPR 200 (w/w)	6	25	100
LacZ	116.3 kDa	Tetramer^vi	7 µM	2	16	130
HK	53.7 kDa	Monomer-Dimer^vii	7 µM	2	16	130
G6P-DH	57.4 kDa	Dimer-Tetramer^viii	4 µM	1	10	80

Molecular weight indicated for subunits. The number of molecules per vesicle is calculated from the internal concentration and volume of the vesicle or lipid-to-protein ratios (for the membrane proteins); we assume a homogeneous distribution of the components over the large-unilamellar vesicles; the enzyme concentrations/numbers reflect those of the subunits and not the structural complexes. The number of molecules of MleP in parenthesis is based on the 50% reconstitution efficiency. ⁱAs determined for homologs of 2HCT family²⁶. ⁱⁱDetermined for homologs^30,31. ⁱⁱⁱTaken from ref. ²⁴. ^ivTaken from ref. ⁹³. ^vTaken from ref. ²⁵. ^viTaken from ref. ⁹⁴. ^viiTaken from ref. ⁹⁵. ^viiiTaken from ref. ⁹⁶.

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