A novel approach to structural analysis of oligonucleotides

A method for determination of the position of guanosine residues in oligodeoxyribonucleotides involving modification with glyoxal

“…The mixture was incubated for 1-2 h at 37°C, then heated for 10 min at 100°C and diluted with bidistilled water to 300-400/al. TCG*TGG TCGTG*G TCGTGG* TCG*TG*G TCG*TGG* TCGTG*G* TCG*TG*G* snake venom phosphodiesterase in borate buffer > Scheme 2 the effect being especially noticeable when the modified base is charged [5]. The presence of a stable negative charge on the modified base made us use only the 'monomodified fraction' for further analysis, because the concomitant di-and polymodified oligonucleotides would have made the interpretation of the results difficult.…”

“…We have previously suggested a method for determination of the positions of base residues in oligonucleotides based on arresting the attack of exonucleases in certain monomer units subjected to specific chemical modification [5,6].…”

“…The chain length of each of these fragments indicates the position of the given base in the starting oligonucleotide (detailed in [5][6][7]). …”

“…This principle is used as a basis for finding the positions of thymidine and cytidine residues in oligonucleotides modified with OsO4 and HSO~ and NH2OCH3, respectively [5,6].…”