2′ Substituted Sergeants Influencing the Deoxy Soldiers in IFolded Oligonucleotides
Jeong-il Park, Shoshannah L. Roth, and D. Tyler McQuade*
Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, 14850
SUPPLEMENTARY INFORMATION
Thermostability of the polymers were compared by measuring the change in intensity of
the CD signal with increasing and decreasing temperature (Table 1S). The melting
temperature of the DNA homopolymer obtained here is a little higher than the result
reported by Jastfer et al.13 and it shows a large hysteresis (20 oC) in the presence of
potassium ion. We note that the difference is not surprising since complete melting for
this polymer does not occur and this lack of complete melting should impose significant
error in the fit of the melting curve (Figure 2S).
TABLE 1S.
Oligonucleotides
Oxy28
Metal
Tm (ºC)
Ta (ºC)
Hysteresis
Na+
67 ± 1
64. ± 1
3
K+
95 ± 2
75 ± 2
20
Na+
60 ± 1
54 ± 1
6
K+
>95
>95
n.a.
Na+
45 ± 1
38 ± 1
7
K+
84 ± 0
68 ± 1
16
Na+
44 ± 1
41 ± 0
2
K+
83 ± 0
71 ± 1
12
Na+
53 ± 0
51 ± 1
2
K+
75 ± 1
70 ± 1
5
Na+
55 ± 0
52 ± 0
3
K+
76 ± 1
69 ± 1
7
Na+
44 ± 0
43 ± 1
1
K+
n.aa).
n.a.a)
n.a.a)
Na+
58 ± 0
50 ± 1
8
ions
DNA
RNA
2’OMe RNA
2’OMe RNA-DNA
Single 2’OMe
Single 2’OH
2’OMe @ 9,17
2’OMe @ 17,18
+
K
n.a.
a)
n.a.
a)
n.a.a)
Tm, Ta, and Tav represent melting, annealing, and averaged temperatures, respectively.
a)
Multiple transitions
(a)
(b)
1
18
30
16
25
14
20
CRD
CRD
12
10
15
10
8
5
6
0
4
2
-5
0
20
40
60
80
100
200
220
240
o
Temperature ( C)
260
280
300
320
340
Wavelength (nm)
Figure 2. (a) Thermal transition profiles for DNA Oxy28 with 50 mM K+ ion. Melting curves (black circle) and annealing curves
(open circle). (b) CD spectra of DNA Oxy28 with 50 mM K+ ion at 25Error!
line). The CD signal at 295 nm does not disappear completely even at 95 ºC.
2
Not a valid link. (solid line) and 95ºC (dotted