Summary information and primary citation

7d0x; DSSR-derived features in text and JSON formats
NMR solution structures of the DNA minidumbbell formed by 5'-mcttgxmcttg-3'
Wan L, Yi J, Lam SL, Lee HK, Guo P (2021): "5-Methylcytosine Substantially Enhances the Thermal Stability of DNA Minidumbbells." Chemistry, 27, 6740-6747. doi: 10.1002/chem.202005410.
Minidumbbell (MDB) is a recently identified non-B DNA structure which has been proposed to associate with genetic instabilities.  It also serves as a functional structural motif in DNA nanotechnology.  DNA molecular switches constructed using MDBs show instant and complete structural conversions with easy manipulations.  The availability of stable MDBs can broaden their applications.  In this work, we found that substitutions of cytosine with 5-methylcytosine could lead to a significant enhancement in the thermal stabilities of MDBs.  Consecutive methylations of cytosine in MDBs brought about cumulative stabilization with a drastic increase in the melting temperature by 23 °C.  NMR solution structures of two MDBs containing 5-methylcytosine residues have been successfully determined and revealed that the enhanced stabilities resulted primarily from favorable hydrophobic contacts, more stable base pairs and enhanced base-base stackings involving the methyl groups of 5-methylcytosine.

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