Gemeinsam stärker: metabolische Arbeitsteilung bei Bakterien(S. 592)
Microorganisms frequently engage in reciprocal cross-feeding inter - actions, in which two or more bacterial strains exchange essential metabolites. Benefits stemming from losing the biosynthetic capabilities to produce certain metabolites likely drive the emergence of these metabolic interdependencies. By using nanotubes, bacteria can effectively exchange nutrients with other cells and – in this way – divide metabolic functions within microbial communities.
Architektur eines Heterochromatinkomplexes(S. 597)
Ann E. Ehrenhofer-Murray
The regulation of gene expression in eukaryotes is achieved by differential chromatin packaging of the genome. Heterochromatin constitutes a repressive type of chromatin in which non-histone proteins bind to the chromatin fibre and restrict gene expression. The silent information regulator (SIR) complex from Saccharomyces cerevisiae serves as a model for eukaryotic heterochromatin. Here, our current structural knowledge of SIR-mediated chromatin is discussed.
Membrandomänen in Bakterien – Ordnung muss sein(S. 600)
Marc Bramkamp, Juri N. Bach
Biological membranes show a high degree of lateral organization. Proteins and lipids are arranged in spatio-temporal domains, termed lipid rafts. Bacterial lipid rafts are stabilized by flotillins and harbor a distinct set of proteins involved in transport, signal transduction, energy metabolism, cell wall homeostasis, and protein secretion. Bacterial model organisms such as Bacillus subtilis emerge as excellent tools to address fundamental questions related to membrane compartmentalization.
Regulation der endosomalen und lysosomalen Biogenese(S. 604)
Lars Langemeyer, Christian Ungermann
Eukaryotic cells use the endocytic pathway to downregulate cell surface receptors or to take up nutrients from the outside, which are finally degraded in the lysosome. The machinery to degrade these components is also transported to lysosomes. Both pathways merge at the endosome, an organelle that undergoes massive membrane remodelling to remove proteins from its surface. Within this review, we will summarize our insights and approaches to unravel molecular mechanism of endosomal and lysosomal biogenesis.
Ubiquitin-Proteasom-gesteuerte Regulation und Qualitätskontrolle der Zelle(S. 608)
Dieter H. Wolf, Ruth Menssen
Protein degradation by the ubiquitin-proteasome system (UPS) is essential for life. Degradation of enzymes and other regulatory proteins like activators or inhibitors is crucial for a multitude of cellular processes. Prominent examples are cell cycle progression or regulation of metabolic pathways. Furthermore, elimination of misfolded proteins is essential to prevent disturbance of cell functions.
Lichtgesteuerte Genexpression auf Einzelzellebene(S. 612)
Dennis Binder, Christopher Probst, Claus bier, Anita Loeschke, Alexander Grünberger
Photocaged compounds are light-responsive biomolecules that regain their primal function upon short light exposure. Thus, cellular functions such as bacterial gene expression can be non-invasively triggered in a gradual and homogenous fashion by light. Especially for single-cell research, optogenetic tools exhibit an enormous potential for achieving an accurate and straightforward control of parallelized expression cultures as shown here with photocaged Isopropyl-β-D-thioalactopyranoside (IPTG) in Escherichia coli.
Lab-on-a-chip-Systementwicklung für den Laboralltag(S. 617)
Thomas Henkel, Nils Gleichmann
Miniaturization of biological and chemical assays in lab-on-a-chip systems is a highly topical field of research. Full custom centric design of dropletbased microfluidic lab-on-a-chip systems leads to a high system integration level and design complexity. We report on a software toolkit for mo - delling droplet traffic and processing for complex microfluidic networks. As a result, the advantages of lab-on-a-chip systems will be accessible for more people through the easy, versatile and efficient transformation of complicated laboratory workflows to easy to use lab-on-a-chip applications.
Mikrofluidische Automatisierung in der Molekulardiagnostik(S. 622)
Gregor Czilwik, Daniel Baumann, Daniel Mark, Roland Zengerle, Felix von Stetten
Easy-to-use point-of-care (POC) tests provide rapid diagnostic results near the patient, enabling fast decision-making in patient management. However, the implementation of automated molecular diagnostic POC tests still faces technical challenges. We demonstrate a highly sensitive POC platform for automated molecular diagnostics of neonatal sepsis that uses a mobile analyzer and unit-use test carriers.
Technologietransfer zur Automatisierung manueller Laborprozesse(S. 625)
Jessica Kopf, Mario Bott, Andreas Traube
Automated laboratory devices and systems are indispensable tools for innovative life science processes. Users, however, face major challenges, such as increasing process complexity, regulatory requirements and individualized production or mass customization. In line, the complexity of process transfers of the manual protocol is constantly increasing. Thus, special effort is required to implement smart automation strategies by concomitant hardware development and process transfer strategies.
Anwendungen & Produkte
Funktionale Membranproteine durch optimierte Lipidumgebung in Nanodiscs(S. 640)
Frank Bernhard, Erik henrich, Barbara Maertens
Membrane proteins are highly relevant for pharmaceutical research, but their biophysical properties pose tremendous difficulties for the preparation of high quality samples. Nanodiscs provide versatile tools to stabilize membrane proteins in defined phospholipid bilayers. A screening platform based on cell-free biosynthesis allows to identify ideal nanodisc/ lipid combinations for the efficient folding, stabilization, and functional characterization of a large diversity of membrane proteins.
Pichia pastoris als Expressions-Plattform für die industrielle Anwendung(S. 643)
Ulrich Giesecke, Ansgar Stratmann
The industrial use of proteins requires a cost-efficient, reliable and robust technology to guarantee the production on high yield. The expressionplatform Pichia pastoris has documented several times his outstanding capacity for heterologous protein production. The flexible choice of location, mode of induction and individual process control results in a useful tool for process development and industrial protein production.
Let’s do it outside: neue Biokatalysatoren mittels surface display(S. 668)
Iasson E. P. Tozakidis, Paul Quehl, Jan Schüürmann, Joachim Jose
Despite their benefits, laborious preparation and purification procedures often make enzymes too expensive to be economically applicable. These efforts can be significantly reduced by immobilizing the enzymes on a microbial cell surface and employing the producing cells directly in the reaction. Here, we present recent progress made with autodisplay, an intensively used surface display technique for Gram-negative bacteria with some unique features that enable access to also difficult enzymes.
Methanol als alternative Kohlenstoffquelle für mikrobielle Produktionsprozesse(S. 672)
Markus Buchhaupt, Jens Schrader
Methanol is an attractive alternative carbon source for industrial biotechnology. Methylobacterium species represent suitable microorganisms to convert methanol into valuable multi-carbon chemicals, as their complex central metabolism provides many different useful starting intermediates for establishing efficient production pathways. Here we describe recent results to produce dicarboxylic acids and terpenoids in M. extorquens.