NAD-modifizierte RNA: Redoxbiochemie trifft RNA-Prozessierung(S. 680)
Andres Jäschke, Katharina Höfer
RNA is an important regulator in biology. Its simple architecture is augmented by diverse chemical modifications. Recently we discovered the ubiquitous redox coenzyme nicotinamide adenine dinucleotide (NAD) to be attached to a specific set of regulatory RNAs in bacteria in a cap-like manner, and to modulate the cellular functions of these RNAs. This article highlights the biosynthesis, removal, and biological function of this novel RNA modification.
Peptid-codierende kleine RNAs in Bakterien(S. 684)
Sabine Brantl, Matthias Gimpel, Inam Ul Haq
Although short open reading frames (sORFs) are present in all genomes, they have often been missed in annotations. Nevertheless, a small variety of peptides involved in different pathways were identified serendipitously and investigated in more detail. Among them are type I toxins, nucleic acid and metal chaperones, membrane components, stabilizing factors of large protein complexes, and regulatory peptides.
Kamel-Antikörper aus dem Reagenzglas(S. 688)
Benedikt Kihn, Iwan Zimmermann, Roger J. P. Dawson, Markus A. Seeger, Eric R. Geertsma
The mechanistic characterization of membrane proteins requires their stabilization in specific conformations. Camelid single-domain antibodies are particularly suited for this purpose due to their unconventional design. However, their broad deployability is prevented as their generation relies on immunization. To overcome this, we developed an in vitro procedure for the generation of single-domain antibodies that allows selection on delicate proteins, such as membrane proteins.
Millionenfach beschleunigte Evolution für maßgeschneiderte Proteine(S. 691)
The Nobel Prize 2018 in chemistry honors three pioneers in directed evolution for their fundamental work on developing methodologies and tailoring proteins to applications demands. Prof. Frances H. Arnold was honored for the directed evolution of enzymes, and George P. Smith as well as Sir Gregory P. Winter for their pioneering work on phage display of peptides and antibodies. This article focuses on the two core technologies of directed evolution and its applications in enzyme catalysis.
Massenspektrometrie in der Biomedizin- und Pharmaforschung(S. 694)
Qiuqin Zhou, Carina Ramallo Guevara, Carsten Hopf
Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) is a label-free technology for spatially resolved analysis of multiple compounds of interest in tissue sections. More specifically, MALDI-MSI enables visualization of spatial distributions of proteins, lipids, metabolites and drugs at cellular resolution. This innovative approach is successfully used in life sciences and biomedical/pharmaceutical research, for example as a sensitive tool for identification of sitespecific biomarkers.
Autonome Lichtproduktion in Bakterien mit optimiertem ilux-Operon(S. 697)
Bioluminescence emission allows the direct visualization of living cells without external light. Its generation usually requires addition of a luciferin, except for bacterial bioluminescence with the lux operon where synthesis and recycling of the luciferin are performed by enzymatic reactions in the cell. An improved ilux operon produces brighter bioluminescence and enables autonomous bioluminescence imaging with increased sensitivity, allowing the observation of single Escherichia coli cells.
Genomveränderungen – CRISPR/Cas9 als Methode der Wahl oder Qual?(S. 701)
Elitsa Y. Dimova, Thomas Kietzmann
The last years showed the rise of CRISPR/Cas9 to stardom. Several features such as programmability, specificity, and efficiency, make it to be a technique of choice for genome editing even in processes where basic aspects are not understood. However, scientific, technical and society driven challenges remain. To cope with these challenges, further research, technological improvements, translational studies as well as an open exchange between laboratories and the society are required.
Vielfältige Genscheren: natürliche Aktivitäten von CRISPR-Cas-Systemen(S. 704)
Lennart Randau, Hanna Müller-Esparza, Daniel Gleditzsch
Prokaryotic genomes often contain CRISPR-Cas systems that enable RNAguided defense against viral attacks. Viral genomes were found to encode anti-CRISPR proteins that inactivate specific Cas protein functions. In the last years, a large variety of CRISPR-Cas system components and mechanisms has been uncovered. This diversity highlights the fact that CRISPRCas systems co-evolve with anti-CRISPR measures, but also indicates that they can adopt roles in the cell that extend beyond viral defense.
Editierung induzierter pluripotenter Stammzellen mittels CRISPR/Cas9(S. 707)
Susan Sgodda, Thomas Cantz
The rapid development of the new genome editing technique CRISPR/ Cas9 enables easy and efficient modifications to the human genome. In combination with autologous cell transplants derived from induced pluripotent stem cells, a versatile platform for individualised cell therapies is entering pre-clinical evaluation.
Anwendungen & Produkte
Herstellung von Nanopartikeln zur Wirkstoffapplikation(S. 720)
Ulrich Massing, Wolfgang Krämer, Benedikt Deuringer, Martin Hagedorn, Vittorio Ziroli
A promising way to test poorly soluble active pharmaceutical ingredients (API) in cell culture or in animals is their application as nanoparticles. Dual centrifugation is a new technique to prepare those nanoparticles – nanosuspensions (nanocrystals), liposomes and emulsions. Nanoparticle preparation takes place in small and tightly closed vials, which allows sterile preparations and very small batch sizes. Since up to 40 samples can be processed in parallel, a new dual centrifuge can be used as screening tool.