Anja Blümler, Harald Schwalbe, Alexander Heckel
Angew. Chem. Int. Ed.
https://doi.org/10.1002/anie.202111613
Here, we present a multi-cycle chemoenzymatic synthesis of modified RNA with simplified solid-phase handling to overcome size limitations of RNA synthesis. It combines the advantages of classical chemical solid-phase synthesis and enzymatic synthesis methods using magnetic streptavidin beads and biotinylated RNA. Successful introduction of light-controllable RNA nucleotides into the tRNAMet sequence was confirmed by gel electrophoresis and mass spectrometry. The methods tolerate modifications in the RNA phosphodiester backbone and allow introductions of photocaged and photoswitchable nucleotides as well as photocleavable strand breaks and fluorophores.

Patricia Müller, Marlen Sahlbach, Simone Gasper, Prof. Dr. Günter Mayer, Priv.-Doz. Dr. Jens Müller, Prof. Dr. Bernd Pötzsch, Prof. Dr. Alexander Heckel
Angew. Chem. Int. Ed. 2021, 60, 22441.
https://doi.org/10.1002/anie.202108468 (open access)
An engineered aptamer with a Cy7-based photocleavable linker can be used as anticoagulant. With tissue-penetrating red light, the aptamer is cleaved, and blood clotting is restored in human whole blood.

Lea Anhäuser, Nils Klöcker, Fabian Muttach, Florian Mäsing, Petr Špaček, Armido Studer and Andrea Rentmeister
Angewandte Chemie International Edition 2020, 59, 3161-3165.
https://doi.org/10.1002/anie.201914573 (open access)
Aryl ketones are photolabile caging groups if installed at the N7 position of guanosine or the N1 position of adenosine whereas common photocaging groups derived from the ortho‐nitrobenzyl moiety were not suitable.

M. Klika Škopić, K. Götte, C. Gramse, M. Dieter, S. Pospich, S. Raunser, R. Weberskirch, A. Brunschweiger
https://doi.org/10.1021/jacs.9b05696
DNA-encoded libraries are increasingly used of drug identification. However, the reactivity of the DNA imposes limitations on the choice of chemical methods for encoded library synthesis. Amphiphilic block copolymers covalently functionalized with sulfonic acid moieties in the lipophilic portion assemble in water and locate the Brønsted catalyst in micelles. These acid nanoreactors enabled the reaction of DNA-conjugated aldehydes to diverse substituted tetrahydroquinolines and aminoimidazopyridines by Povarov and Groebke–Blackburn–Bienaymé reactions, respectively.

Bastian Joffroy, Yavuz O. Uca, Domen Prešern, Jonathan P. K. Doye, Thorsten L. Schmidt
Nucleic Acids Res. 2018, DOI:10.1093/nar/gkx1238
Small DNA circles can serve as templates for rolling circle amplification (RCA), which is a common and extremely robust amplification mechanism for nucleic acids. We discovered a strong template length-dependent amplification efficiency bias of RCA with the same periodicity as B-DNA.
