Dataset Information


Structure and Biophysics for a Six Letter DNA Alphabet that Includes Imidazo[1,2-a]-1,3,5-triazine-2(8H)-4(3H)-dione (X) and 2,4-Diaminopyrimidine (K).

ABSTRACT: A goal of synthetic biology is to develop new nucleobases that retain the desirable properties of natural nucleobases at the same time as expanding the genetic alphabet. The nonstandard Watson-Crick pair between imidazo[1,2-a]-1,3,5-triazine-2(8H)-4(3H)-dione (X) and 2,4-diaminopyrimidine (K) does exactly this, pairing via complementary arrangements of hydrogen bonding in these two nucleobases, which do not complement any natural nucleobase. Here, we report the crystal structure of a duplex DNA oligonucleotide in B-form including two consecutive X:K pairs in GATCXK DNA determined as a host-guest complex at 1.75 Å resolution. X:K pairs have significant propeller twist angles, similar to those observed for A:T pairs, and a calculated hydrogen bonding pairing energy that is weaker than that of A:T. Thus, although inclusion of X:K pairs results in a duplex DNA structure that is globally similar to that of an analogous G:C structure, the X:K pairs locally and energetically more closely resemble A:T pairs.


PROVIDER: S-EPMC5831194 | BioStudies | 2017-01-01

REPOSITORIES: biostudies

Similar Datasets

2015-01-01 | S-EPMC4633024 | BioStudies
1000-01-01 | S-EPMC419603 | BioStudies
2007-01-01 | S-EPMC2536688 | BioStudies
2008-01-01 | S-EPMC2816004 | BioStudies
1000-01-01 | S-EPMC4222377 | BioStudies
2013-01-01 | S-EPMC3844552 | BioStudies
2012-01-01 | S-EPMC3525050 | BioStudies
2018-01-01 | S-EPMC5756560 | BioStudies
2020-01-01 | S-EPMC7549732 | BioStudies
2003-01-01 | S-EPMC152993 | BioStudies