Negative charge at the 3'-terminus of oligonucleotides and resistance to venom exonuclease

Identification of bifunctional GA and AG intrastrand crosslinks formed between cisplatin and DNA

“…These results support the conclusion that phosphodiesterase I has some 5 0 -exonuclease activity, although they could also be explained by the presence of small amounts of an impurity with this activity. Support for the former explanation is provided by other studies that have reported phosphodiesterase I has the ability to hydrolyse nucleotides from the 5 0 end of oligonucleotides [36,37]. …”

Specificity of deoxyribonuclease from salmon testes

“…One of the differences between preparation A and prepa-ELUTION VOLUME, ml figure 5: Elution profile of a hydrolysate of an aliquot of heptanucleotides (3.5 FI254 units). The hydrolysis was performed in 1 m NH4OH according to Richards and Laskowski (1969a). The hydrolysate was diluted 1:10 with water and applied to a DEAE-cellulose column (0.S X 24 cm).…”

“…The exonuclease digestion of oligomers bearing 3'-monophosphate was performed at pH 6.2 (Richards and Laskowski, 1969a). It was carried out as described by Duch et al (1973).…”

Sequencing Oligonucleotides with Blocked Termini Using Exonuclease Digestion and Electrospray Mass Spectrometry

“…Originally, 3Ј-modified ODNs were classified as totally resistant to SVP digestion (54). Later, Richards and Laskowski (55) found that SVPs degrade 3Ј-phosphorylated ODNs, but very slowly. For example, digestion of 3Ј-phosphorylated trimer ODNs was reported to be about 1000 times slower than that of a dephosphorylated analog.…”

“…As is known (55), at the optimal digestion pH of 9.4, k a Ӷ k b , k b Ϸ k c , the cleavage of the 3Ј-labeled nucleotide is very slow and the cleavage of nucleotides from the truncated ODNs is much faster. Thus the truncated ODNs (B, C, D, .…”