UV melting

An abasic peptide (Ac-Gys -Lys-(Ser-Ala-Ala-Lys)4-Ser-Gly-Lys-NH2) with unmodified Ser residues was synthesized and used as a control. No induced cooperative binding to. TAjGsAsT) was observed in the UV melting curve with this abasic peptide. This indicated that the cooperative melting between aPNA and its complementary DNA was not merely a reflection of nonspecific interactions be-... 

Tab. 5.3 UV melting data for hydrophobic N-capped B5 aPNA DNA complexes...

CD and UV melting profiles in the presence of the ligands were carried ont to confirm the presence of a DNA-RNA hybrid duplex in the presence of the ligands. The addition of 2.2 tiM of neomycin and ethidium bromide results in a increase of 12°C, whereas the addition of 6 resnlts in a increase of 20°C. Increased concentration of 6 caused a gradual increase in the hybrid melting temperature. As the concentration of NM was increased from 0 p.M to 3 p.M, the melting temperature of the hybrid increases from 48.9°C to 70.1°C, a 21.2°C increase overall. 

The derivation of In Kohs from UV melting profiles depends on the extrapolation of In Kohs to a temperature different than the Tm using a value of AII°... 

Tm data are from UV-melting curves (260 nm) of duplex with antiparallel component. 

Table 7. UV Melting Curves for Four Pyranosyl Oligonucleotides...

As shown by a UV melting experiment, successful triplex formation can be achieved when this inverted triad is accommodated in T AT triplexes. The two A moieties in the inverted repeat are not likely to be identical, and the issue is yet to be resolved as to whether the two have different glycosidic torsions and so on. These examples involving pseudopyrimidines in the central position have really extended the triplex recognition motifs and allow the construction of additional patterns with pyrimidines involved in nonstandard WC pairs. 

Thermal denaturation of DNA (UV melting curve). A solution of double-stranded DNA was placed in a spectrophotometer and the change in absorbance at 260 nm was measured as the temperature of the sample... 

M. P. McPike, J. M. Sullivan, J. Goodisman, and J. C. Dabrowiak, Footprinting, circular dichroism and UV melting studies on neomycin B binding to the packaging region of human immunodeficiency virus type-1 RNA, Nucleic Acids Res., 30 (2002) 2825-2831. 

The same compound was used by our group before in peptide chemistry and a crystal structure has been reported. The stability of metallated ODNs with complementary DNA or RNA has been investigated by UV melting studies. ... 

Thermal denaturation studies of DNA and DNA-protein complexes are performed on a UV spectrophotometer equipped with temperature controlled cell holders. Melting of the DNA duplex is indicated by a cooperative hyperchromism at 260 nm. Stabilization by Sac7d is most readily observed with poly[d(AT)]-poly[d(AT)] because of its intrinsic low stability, especially in low salt. The UV melting curve of poly[d(AT)] poly[d(AT)] in 0.01 M K2HPO4 is sharp with a Tm of 43.5° (Fig. 9). In the presence of Sac7d, the melting profile of poly[d(AT)]-poly [d(AT)] broadens and the Tm increases by as much as 33°C for solutions with an excess of Sac7d. The observed Tm for the complex depends on the concentration of protein. 

Table H. Comparison of Td(l/2) By DSC, EFISH and UV Compound Temp Rel. EFISH Rel. UV melt endo decomp, exo...

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