TY  - JOUR
A1  - Olejko, Lydia
A1  - Cywinski, Piotr J.
A1  - Bald, Ilko
T1  - Ion-Selective formation of a guanine quadruplex on DNA origami structures
JF  - Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition
N2  - DNA origami nanostructures are a versatile tool that can be used to arrange functionalities with high local control to study molecular processes at a single-molecule level. Here, we demonstrate that DNA origami substrates can be used to suppress the formation of specific guanine (G) quadruplex structures from telomeric DNA. The folding of telomeres into G-quadruplex structures in the presence of monovalent cations (e.g. Na+ and K+) is currently used for the detection of K+ ions, however, with insufficient selectivity towards Na+. By means of FRET between two suitable dyes attached to the 3- and 5-ends of telomeric DNA we demonstrate that the formation of G-quadruplexes on DNA origami templates in the presence of sodium ions is suppressed due to steric hindrance. Hence, telomeric DNA attached to DNA origami structures represents a highly sensitive and selective detection tool for potassium ions even in the presence of high concentrations of sodium ions.
KW  - DNA nanotechnology
KW  - FRET
KW  - G-quadruplexes
KW  - nanostructures
KW  - self-assembly
Y1  - 2015
U6  - https://doi.org/10.1002/anie.201409278
SN  - 1433-7851
SN  - 1521-3773
VL  - 54
IS  - 2
SP  - 673
EP  - 677
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Kedracki, Dawid
A1  - Filippov, Sergey K.
A1  - Gour, Nidhi
A1  - Schlaad, Helmut
A1  - Nardin, Corinne
T1  - Formation of DNA-Copolymer Fibrils Through an Amyloid-Like Nucleation Polymerization Mechanism
JF  - Macromolecular rapid communications
N2  - Conjugation of a hydrophobic poly(2-oxazoline) bearing tertiary amide groups along its backbone with a short single stranded nucleotide sequence results in an amphiphilic comb/graft copolymer, which organizes in fibrils upon direct dissolution in water. Supported by circular dichroism, atomic force microscopy, transmission electron microscopy, and scattering data, fibrils are formed through inter- and intramolecular hydrogen bonding between hydrogen accepting amide groups along the polymer backbone and hydrogen donating nucleic acid grafts leading to the formation of hollow tubes.
KW  - DNA copolymers
KW  - fibers
KW  - hydrogen bonding
KW  - nucleation polymerization
KW  - self-assembly
Y1  - 2015
U6  - https://doi.org/10.1002/marc.201400728
SN  - 1022-1336
SN  - 1521-3927
VL  - 36
IS  - 8
SP  - 768
EP  - 773
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Brosnan, Sarah M.
A1  - Schlaad, Helmut
A1  - Antonietti, Markus
T1  - Aqueous Self-Assembly of Purely Hydrophilic Block Copolymers into Giant Vesicles
JF  - Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker ; International edition
N2  - Self-assembly of macromolecules is fundamental to life itself, and historically, these systems have been primitively mimicked by the development of amphiphilic systems, driven by the hydrophobic effect. Herein, we demonstrate that self-assembly of purely hydrophilic systems can be readily achieved with similar ease and success. We have synthesized double hydrophilic block copolymers from polysaccharides and poly(ethylene oxide) or poly(sarcosine) to yield high molar mass diblock copolymers through oxime chemistry. These hydrophilic materials can easily assemble into nanosized (<500nm) and microsized (>5m) polymeric vesicles depending on concentration and diblock composition. Because of the solely hydrophilic nature of these materials, we expect them to be extraordinarily water permeable systems that would be well suited for use as cellular mimics.
KW  - block copolymers
KW  - polymersomes
KW  - polysaccharides
KW  - self-assembly
KW  - vesicles
Y1  - 2015
U6  - https://doi.org/10.1002/anie.201502100
SN  - 1433-7851
SN  - 1521-3773
VL  - 54
IS  - 33
SP  - 9715
EP  - 9718
PB  - Wiley-VCH
CY  - Weinheim
ER  -