Biomedical Engineering Reference
In-Depth Information
Table 13.5: Binding rate coefficient and fractal dimensions for (a) electrochemical
detection of wild-type Saccharomyces cerevisia responses to estrogen (
Baronian and
Guruzada, 2007
), and real-time monitoring of restriction endonuclease activity using
a molecular beacon (
Ma et al., 2007
).
Analyte in Solution/Receptor on Surface
k
D
f
(a) EBP (estrogen binding protein) in Saccaromyces cervisiae
159.24
2.91
1.6944
0.0348
17
-estradiol
161.42
4.81
2.1904
0.05646
b
(b) 32 U endonuclease/molecular beacon
6.677
0.344
1.7436
0.0398
25 U endonuclease/molecular beacon
6.351
0.379
1.7376
0.0398
10 U endonuclease/molecular beacon
0.5446
0.0048
0.972
0.0104
4 U endonuclease/molecular beacon
0.34 0.0
1.0 0.0
in the sequencing of large strands of DNA (
Bhagwat, 1992; Pingouid and Jeltsch, 2001
). Due
to their biological importance, assays for restriction endonucleases are essential (
Ma et al.,
2007
).
Ma et al. (2007)
have recently used a MB for the real-time monitoring of restriction
endonuclease activity. MBs have been used in biology, biotechnology, chemistry, and in
medical science for biomolecular recognition due to their high selectivity and excellent spec-
ificity (
Tyagi et al., 1998; Tan et al., 2004
). MB may also be used to monitor DNA-protein
interactions (
Tang et al., 2003, 2005
; Lin et al., 2005).
Ma et al. (2007)
developed a novel
approach for the real-time monitoring of
Rsa
I endonuclease activity based on the primer
extension reaction using MB.
Figure 13.6a
shows the real-time monitoring of the DNA cleavage process catalyzed by
32 units of
Rsa
I endonuclease. A single-fractal analysis is adequate to describe the binding
reaction. The values of the binding rate coefficient
k
and the fractal dimension
D
f
for a
single-fractal analysis are given in
Table 13.5
.
Figure 13.6b
shows the real-time monitoring of the DNA cleavage process catalyzed by
25 units of
Rsa
I endonuclease. Once again, a single-fractal analysis is adequate to describe
the binding reaction. The values of the binding rate coefficient
k
and the fractal dimension
D
f
for a single-fractal analysis are given in
Table 13.5
.Itisofinteresttonotethata
decrease in the restriction endonuclease activity from 32 to 25 Units of activity decreases
the binding rate coefficient
k
from a value of 6.677 to 6.351. Note that a change in the
restriction endonuclease activity (U) and in the binding rate coefficient are in the same
direction.
Figure 13.6c
shows the real-time monitoring of the DNA cleavage process catalyzed by
10 units of
Rsa
I endonuclease. Once again, a single-fractal analysis is adequate to describe
the binding reaction. The values of the binding rate coefficient,
k
and the fractal dimension,
D
f
for a single-fractal analysis are given in
Table 13.5
.
