Sulfate transport?
Renal sulfate transport occurs via a sulfate/bicarbonate exchange process.
!!
Misregulation of sulfate transport is present in a number of disease states including Alzheimer’s
disease.
Hofmeister seriesorganic anions > ClO4
- > SCN- > I- > NO3- > Br- > Cl- >
HCO3-> H2PO4
- > F-, SO42- > HPO4
2-
...orders anions in terms of their hydrophobicityF. Hofmeister, Arch. Exp. Patol. Phamakol. 1888, 24, 247.
Hydration energy
Anion ΔGh(X-) (kJmol-1)
NO3- -314
Cl- -338
HCO3- -388
SO42- -1103
B.A. Moyer et al. in Supramolecular Chemistry of Anions, Eds. A. Bianchi, K. Bowman-James and E. García-España, Wiley, 1997.
SO42-
phosphate buffer pH 7.2
Bicarbonate transport studies
HCO3-
pulse at 120s
Cl-
Chloride efflux promoted by 1-5 (2 % molar carrier to lipid) from unilamellar POPC vesicles loaded with 450 mM NaCl buffered to pH 7.2 with 20 mM sodium phosphate salts. The vesicles were dispersed in 162 mM Na2SO4 buffered to pH 7.2 with 20 mM sodium phosphate salts. At t = 120 s, a solution of NaHCO3 was added to give a 40 mM external concentration. At the end of the experiment, detergent was added to lyse the vesicles and calibrate the ISE to 100 % chloride efflux. Each point represents the
average of three trials. DMSO was used as control.
NH N HN
HNNH
HN
HN
R
RR
X
X
X1 X = O, R = Ph2 X = O, R = p-C6H4F3 X = O, R = C6F5
4 X = O, R = p-C6H4(CF3)2
5 X = O R=
CF3
CF3
SO42-
phosphate buffer pH 7.2
Sulfate transport?
HCO3-
pulse at 120s
Cl-
Chloride efflux promoted by 1-5 (2 % molar carrier to lipid) from unilamellar POPC vesicles loaded with 450 mM NaCl buffered to pH 7.2 with 20 mM sodium phosphate salts. The vesicles were dispersed in 162 mM Na2SO4 buffered to pH 7.2 with 20 mM sodium phosphate salts. At t = 120 s, a solution of NaHCO3 was added to give a 40 mM external concentration. At the end of the experiment, detergent was added to lyse the vesicles and calibrate the ISE to 100 % chloride efflux. Each point represents the
average of three trials. DMSO was used as control.
NH N HN
HNNH
HN
HN
R
RR
X
X
X6 X = S, R = Ph7 X = S, R = p-C6H4F8 X = S, R = C6F5
9 X = S, R = p-C6H4(CF3)2
10 X = S, R=
CF3
CF3
Lucigenin assay
Cl-
SO42- lucigenin Evidence for transmembrane transport of sulfate. Unilamellar POPC vesicles were loaded with 100
mM NaCl and 2 mM lucigenin buffered to pH 7.2 with 20 mM sodium phosphate salts and dispersed in a 100 mM NaCl solution (buffered to pH 7.2). At t = 30 s, a solution of the
appropriate anion was added (final concentration of 40 mM NaNO3 (red), 40 mM Na2SO4 (green) or 40 mM NaCl (blue)). At t = 60 s, a methanol solution of the putative transporter was added (2 %
molar carrier to lipid). At the end of the experiment (240 s), detergent was added to lyse the vesicles. Each point represents the average of three trials. A blank experiment was performed by
addition of Na2SO4, followed by addition of methanol; (a) compound 8.
N. Busschaert, M. Wenzel, M.E. Light, P.I. Hernadez, R. Perez-Tomas and P.A. Gale, J. Am. Chem. Soc. 2011, 133, 14136.
Cl-
NH N HN
HNNH
HN
HN
S
S
SF
F
F
F
F F
F
FF
F
FF
F
FF
Cyclic peptide-based receptors
NOO
NH N
O
HN OHN
NO
O
NH
S NH
HN
HNS
NH
NHS
N
8
NOO
NH N
O
HN OHN
NO
O
NHS NH
HN
HN S
NH
NHS
9
NOO
NH N
O
HN OHN
NO
O
NH
S NH
HN
HNS
NH
NHS
7
N. Busschaert, L.E. Karagiannidis, M. Wenzel, C.J.E. Haynes, N.J. Wells, P.G. Young, D. Makuc, J. Plavec, K.A. Jolliffe and P.A. Gale, Chem. Sci. 2014, DOI:10.1039/C3SC52006D.
Cl-/NO3- antiport
NOO
NH N
O
HN OHN
NO
O
NH
S NH
HN
HNS
NH
NHS
N
8
NOO
NH N
O
HN OHN
NO
O
NHS NH
HN
HN S
NH
NHS
9
NOO
NH N
O
HN OHN
NO
O
NH
S NH
HN
HNS
NH
NHS
7
NO3-Cl-
phosphate buffer pH 7.2
4% molar carrier to lipid
NOO
NH N
O
HN OHN
NO
O
NH
S NH
HN
HNS
NH
NHS
N
8
NOO
NH N
O
HN OHN
NO
O
NHS NH
HN
HN S
NH
NHS
9
NOO
NH N
O
HN OHN
NO
O
NH
S NH
HN
HNS
NH
NHS
7
Cl-/HCO3- antiportHCO3
- pulse at 120sCl-
phosphate buffer pH 7.2
SO42-
4% molar carrier to lipid
Lucigenin assay
NOO
NH N
O
HN OHN
NO
O
NHS NH
HN
HN S
NH
NHS
9
Cl-
SO42-
lucigenin
Cl-
4% molar carrier to lipid
N. Busschaert, L.E. Karagiannidis, M. Wenzel, C.J.E. Haynes, N.J. Wells, P.G. Young, D. Makuc, J. Plavec, K.A. Jolliffe and P.A. Gale, Chem. Sci. 2014, DOI:10.1039/C3SC52006D.
Cl-/SO42- exchange
NOO
NH N
O
HN OHN
NO
O
NH
S NH
HN
HNS
NH
NHS
N
8
NOO
NH N
O
HN OHN
NO
O
NHS NH
HN
HN S
NH
NHS
9
NOO
NH N
O
HN OHN
NO
O
NH
S NH
HN
HNS
NH
NHS
7
NH N HN
HNNH
HN
HN
R
RR
X
X
X
1 X=O R=C6H5 2 X=S R=C6H53 X=O R=C6F5 4 X=S R=C6F5 5 X=O R=m-C6H3(CF3)2 6 X=S R=m-C6H3(CF3)2
4% molar carrier to lipid
N. Busschaert, L.E. Karagiannidis, M. Wenzel, C.J.E. Haynes, N.J. Wells, P.G. Young, D. Makuc, J. Plavec, K.A. Jolliffe and P.A. Gale, Chem. Sci. 2014, DOI:10.1039/C3SC52006D.
13C NMR assay for bicarbonate transport
O
-O
OH
Chloride pulse O
-O
OH
Cl-
+ Carrier
O
-O
OH
Cl-+ Mn2+
O
O-
OH
Cl-
Mn2+
NMR method: J.T. Davis, P.A. Gale, O.A. Okunola, P. Prados,
J.C. Iglesias-Sanchez, T. Torroba and R. Quesada Nature Chem. 2009, 1,
138-144. C&E News April 2009.
NH N HN
HNNH
HN
HN
R
RR
X
X
X 1 X = O, R = n-Bu2 X = O, R = Ph3 X = S, R = n-Bu4 X = S, R = Ph
33S NMR assay
NH N HN
HNNH
HN
HN
S
S
S NH N HN
HNNH
HN
HN
O
O
OF
F
F
F
F F
F
FF
F
FF
F
FF
NH N HN
HNNH
HN
HN
S
S
SF
F
F
F
F F
F
FF
F
FF
F
FF
33S NMR assay
NOO
NH N
O
HN OHN
NO
O
NHS NH
HN
HN S
NH
NHS
9NOO
NH N
O
HN OHN
NO
O
NH
S NH
HN
HNS
NH
NHS
7
33S NMR assay
NH N HN
HNNH
HN
HN
S
S
S NH N HN
HNNH
HN
HN
O
O
OF
F
F
F
F F
F
FF
F
FF
F
FF
NH N HN
HNNH
HN
HN
S
S
SF
F
F
F
F F
F
FF
F
FF
F
FF
33S NMR assay
NOO
NH N
O
HN OHN
NO
O
NHS NH
HN
HN S
NH
NHS
9N
OO
NH N
O
HN OHN
NO
O
NH
S NH
HN
HNS
NH
NHS
7