Probing the MVAI methyltransferase region that interacts with DNA: affinity labeling with the dialdehyde-containing DNA duplexes

Synthesis and properties of phosphorylated 3'-O-beta-D-ribofuranosyl-2'-deoxythymidine

A strategy was developed for the synthesis of 3'-O-beta-D-ribofuranosyl 2'-deoxythymidine derivatives using three different protecting groups, which allows the synthesis of a phosphoramidite building block for oligonucleotide synthesis. Likewise the 5'-O- and 5''-O-phosphorylated analogues were synthesized and their conformation was determined using NMR spectroscopy.

Affinity modification of EcoRII DNA methyltransferase by the dialdehyde-substituted DNA duplexes: mapping the enzyme region that interacts with DNA

Affinity modification of EcoRII DNA methyltransferase (M x EcoRII) by DNA duplexes containing oxidized 2'-O-beta-D-ribofuranosylcytidine (Crib*) or 1-(beta-D-galactopyranosyl)thymine (Tgal*) residues was performed. Cross-linking yields do not change irrespective of whether active Crib* replaces an outer or an inner (target) deoxycytidine within the EcoRII recognition site. Chemical hydrolysis of M x EcoRII in the covalent cross-linked complex with the Tgal*-substituted DNA indicates the region Gly268-Met391 of the methylase that is likely to interact with the DNA sugar-phosphate backbone. Both specific and non-specific DNA interact with the same M x EcoRII region. Our results support the theoretically predicted DNA binding region of M x EcoRII.

An additional 2'-ribofuranose residue at a specific position of the DNA primer prevents Its elongation by HIV-1 reverse transcriptase

Oligodeoxynucleotides containing 2'-O-beta-D-ribofuranosyladenosine were prepared and used as modified primers in RNA-templated DNA synthesis catalyzed by HIV reverse transcriptase. It was shown that the additional 2'-ribofuranose residue in specific position of primer prevents its elongation.