Tautomeric equilibria of isoguanine and related purine analogs.
Nucleobase pairs in DNA match hydrogen-bond donor and acceptor groups on the nucleobases. However, these can adopt more than one tautomeric form, and can consequently pair with nucleobases other than their canonical complements, possibly a source of natural mutation. These issues are now being re-visited by synthetic biologists increasing the number of replicable pairs in DNA by exploiting unnatural hydrogen bonding patterns, where tautomerism can also create mutation. Here, we combine spectroscopic measurements on methylated analogs of isoguanine tautomers and tautomeric mixtures with statistical analyses to a set of isoguanine analogs, the complement of isocytosine, the 5th and 6th "letters" in DNA.
a Foundation for Applied Molecular Evolution (FfAME) , Alachua , FL , USA.
Nilesh B
NB
Karalkar
b Department of Statistics , University of Florida , Gainesville FL , USA.
Kshitij
K
Khare
c Department of Chemistry and Chemical Biology , Indiana University-Purdue University, Indianapolis , Indianapolis , IN , USA.|d ENSCO, Inc. , Melbourne , FL , USA.
Robert
R
Molt
a Foundation for Applied Molecular Evolution (FfAME) , Alachua , FL , USA.
Steven A
SA
Benner
D006147:Guanine / Q000737:chemistry*; D007536:Isomerism; D011687:Purines / Q000737:chemistry*; D013057:Spectrum Analysis
D011687:Purines; D006147:Guanine; C008183:isoguanine; C030985:purine
Isoguanine; artificially expanded genetic information systems; isocytosine; synthetic biology; tautomer; tautomeric ratios