Recognition of selected azoles as degenerate bases by thermus aquaticus DNA polymerase

A series of azole deoxyribonucleosides are presented as candidate universal nucleosides. These compounds were designed to possess the ability to base-pair nonspecifically with the naturally occurring bases in duplex DNA. The base-pairing specificity of these azoles as components of DNA templates was therefore examined. Oligonucleotides containing a single azole base substitution were employed as sense strand PCR primers for the amplification of hisF from Esckerichia coli. The distribution of the four natural deoxyribonucleotides incorporated into the antisense strand opposite the candidate universal base by Thermus Aquaticus DNA polymerase was determined by quantitative cycle sequencing of the double stranded DNA product. Several of the heterocycles were found to base-pair with more than one of the four natural bases. The results of this initial study has prompted the examination of the ahilitv of the rnrresoondinff nucleoside triohosnhates of several of these heterocycles to serve as substrates for DNA polymerase.