Mismatch discrimination of base-modified nucleic acids and their constituents: non-Watson-Crick base pairing induced by tautomerization.
The effect of tautomerism on the mismatch discrimination was studied on 7-deazapurine and 8-aza-7-deazapurine analogues of isoguanosine. 7-Halogenated 7-deaza-2'-deoxyisoguanosines show better base pair discrimination than 2'-deoxyisoguanosine due to the more favored keto tautomer formation. 8-Aza-7-deazaisoguanosine and its 7-halogeno derivatives also show higher keto tautomer population than that of isoguanosine, but the 7-halogens do not bias the tautomeric equilibrium significantly as it is observed for the 7-deaza-2'-deoxyisoguanosine derivatives.
Seela
Frank
F
Laboratorium für Organische und Bioorganische Chemie, Universität Osnabrück, Barbarastrasse 7, 49069 Osnabrück, Germany. Frank.Seela@uni-osnabruck.de
Peng
Xiaohua
X
Xu
Kuiying
K
D000241:Adenosine; D020137:Base Pair Mismatch; D020029:Base Pairing; D006151:Guanosine / Q000737:chemistry*; D007536:Isomerism; D011687:Purines / Q000737:chemistry
C512929:7-deazapurine; D011687:Purines; D006151:Guanosine; C008184:isoguanosine; D000241:Adenosine