Publications (3)0 Total impact
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ABSTRACT: The (L)-a-lyxopyranosyl-(4'yields 3')-oligonucleotide system-a member of a pentopyranosyl oligonucleotide family containing a shortened backbone-is capable of cooperative base-pairing and of cross-pairing with DNA and RNA. In contrast, corresponding (D)-beta-ribopyransoyl-(4' yields 3')-oligonucleotides do not show base-pairing under similar conditions. We conclude that oligonucleotide systems can violate the six-bonds-per-backbone-unit rule by having five bonds instead, if their vicinally bound phosphodiester bridges can assume an antiperiplanar conformation. An additional structural feature that seems relevant to the cross-pairing capability of the (L)-a-lyxopyranosyl-(4' yields 3')-oligonucleotide system is its (small) backbone/basepair axes inclination. An inclination which is similar to that in B-DNA seems to be a prerequisite for an oligonucleotide system s capability to cross-pair with DNA.
02/2001;
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ABSTRACT: To determine whether the remarkable chemical properties of the pyranosyl isomer of RNA as an informational Watson-Crick base-pairing system are unique to the pentopyranosyl-(4 + 2)-oligonucleotide isomer derived from the RNA-building block D-ribose, studies on the entire family of diastereoisomeric pyranosyL(4 - Z)-oligonucleotide systems deriving from D-ribose. L-lyxose. D-xylose, and L-arabinose were carried out. The result of these extended studies is unambiguous: not only pyranosyl-RNA, but all members of the pentopyranosyl(4 + 2)-oligonucleotide family are highly efficient Watson-Crick base-pairing systems. Their synthesis and pairing properties will be described in a series of publications in this journal.
02/2001;
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ABSTRACT: A comparison of relevant properties of selected pyranosyl-RNA and homo-DNA duplexes offers an opportunity for testing the thesis of the predominant role of inter-strand base stacking in oligonucleotide systems with large backbone inclination. Missing base sequences were prepd. and tested. It was found that the sequence dependence of duplex stability in the two pairing systems was, without exception, of opposite directionality. The phenomenon of a quasi-enantio-morphism in the CD spectra of duplexes of a given base sequence in the two systems was also obsd., even though the sense of chirality of the corresponding sugar units in both systems was the same. It is concluded that quasi-linear oligonucleotide systems with strongly inclined backbones represent promising objects of study for detecting and analyzing previously unknown structure-property relationships in nucleic acids. [on SciFinder (R)]
