Alternating DNA and pi-conjugated sequences. Thermophilic foldable polymers.
Foldable polymers with alternating single-strand deoxyribonucleic acid and planar conjugated organic perylene tetracarboxylic diimide units were found to self-organize into loosely folded nanostructures. Upon heating, the loosely folded structures become more ordered as evidenced by pi-stacking in the perylene segments. The folding and unfolding processes driven by the molecular interactions of adjacent perylenes were monitored in both aqueous and organic solutions. Heat-promoted folding, or inverse temperature behavior, which originates from positive enthalpy changes, was only observed in water. Therefore, we attributed this inverse temperature dependence to hydrophobic effects rather than pi-pi molecular orbital overlap between the perylene planes. These findings shed light on the design of new thermophiles in protein engineering as well as the construction of macromolecular-based nanodevices with actuator and sensory properties.
Wang
Wei
W
Department of Chemistry, Washington State University, Pullman, Washington 99164, USA.
Wan
Wei
W
Zhou
Hong-Hui
HH
Niu
Shuqiang
S
Li
Alexander D Q
AD
D001483:Base Sequence; D004277:DNA, Single-Stranded / Q000737:chemistry*; D006358:Hot Temperature; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D016328:NF-kappa B / Q000737:chemistry / Q000235:genetics; D009690:Nucleic Acid Conformation; D010569:Perylene / Q000737:chemistry; D013816:Thermodynamics
D004277:DNA, Single-Stranded; D016328:NF-kappa B; D010569:Perylene