Chemistry Reference
In-Depth Information
Table 7.2
(Continued)
Immobilization
strategy
Properties of the binding/
unbinding process
Receptor
Ligand
Reference
PSGL-1
in human PMN
cells and LS174T human
colon adenocarcinoma
cells
P-selectin
PMN and LS174T cells were im-
mobilized on culture dishes
Silanized cantilevers were coated
with anti-human IgG Fc mono-
clonal antibody and subsequently
with P-selectin-IgG Fc chimera
proteins
Single peak distributions on rupture force histograms were
observed at loading rates from 0.5 to 30
[181]
ms
1
. Force spectra
deviated from linearity in the lower limit of the loading rate.
Values for k
d
(0) and x
b
were 0.20 s
1
and 0.14 nm respectively
for P-selectin/PSGL-1 interactions, and 2.78 s
1
and 0.13 nm
respectively for P-selectin/LS174T ligand interactions. The
lower binding strength of P-selectin to its ligand on LS174T
cells explains the larger rolling velocity measured in
m
ow-
chamber experiments.
Transporter
SGLT
in intact brush
border membrane
vesicles
Inhibitor
phlorizin
Phlorizin was coupled to the tips
via a
The unbinding force for phlorizin-sodium/glucose co-trans-
porter was 120 pN and x
[182]
exible cross-linker
Vesicles were adsorbed onto a
gold surface
was 0.5 nm. Analysis of the wash-out
recovery time of phlorizin binding probability yielded k
d
(0)
b
¼
10
5
s
1
. The on rate k
a
was
10
3
M
1
s
1
leading to an
equilibrium dissociation constant of
5
·
M. Recognition
was sodium dependent and inhibited by D-glucose.
0.2
m
SGLT1 in stably trans-
fected CHO cells
D-glucose
Ligands were conjugated to AFM
tips with a
The mean unbinding force of D-glucose to SGLT1 in the
presence of sodium was about 50 pN at a loading rate of
1 mms
1
. Binding was inhibited in the presence of free sub-
strate D-galactose, free inhibitor phlorizin but not in the
presence of L-glucose.
[183]
exible PEG-
crosslinker
Cells were seeded on poly-L-ly-
sine-coated glass slides
