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Privatrechtliche Haftung ist ein wichtiges Steuerungsinstrument einer dezentral organisierten Wirtschaftsordnung. Anders als Regulierung, die potenziell gefährliche Tätigkeiten ex ante steuert, greift Haftung ex post ein, nachdem ein Schaden oder eine Gefährdungslage bereits eingetreten ist. Die wohlfahrtsmindernde Überregulierung von Tätigkeiten, die in Wahrheit gar nicht oder nur in geringem Umfang schadensträchtig sind, lässt sich dadurch vermeiden. Trotzdem generiert auch Haftung Anreize zum sorgfältigen, schadensvermeidenden Verhalten ex ante. Für die Wirksamkeit des Steuerungseffekts ist es essentiell, dass diejenigen Akteure haftungsrechtlich adressiert werden, die zur Kontrolle der jeweiligen Gefahr am besten in der Lage sind. Die Digitalisierung stellt das Haftungsrecht insofern vor Herausforderungen als neue Akteure die Bühne betreten, die als potenzielle Haftungssubjekte infrage kommen, nämlich Roboter und andere autonome Systeme sowie Plattformen, die das Internet erschließen und Nutzer miteinander in Kontakt bringen. Der folgende Beitrag analysiert die Haftungsverfassung digitaler Märkte im Hinblick auf die Verantwortung für autonome Systeme und digitale Plattformen.

Building on the motivation–ability (MA) theoretical framework, we develop a motivation–trust–vulnerability (MTV) framework to explain behavioral decision making in situations of uncertainty and vulnerability. We apply our new framework to cross-border online shopping, which is characterized by uncertain benefits, potential losses, and increased vulnerability of making cross-border online purchases at foreign online vendors. The MTV framework (1) explains the mechanism of cross-border online shopping by considering the effects and interactions of motivation, trust, and vulnerability (2), offers a new conceptualization of perceived vulnerability and (3) is applicable to culturally and economically distinct country markets. The findings from two major e-commerce markets (China and Germany; N = 808) support our framework and suggest that perceived vulnerability acts as an obstacle that prevents consumers from cross-border online shopping. However, in interaction with trust towards foreign online vendors perceived vulnerability positively affects the relationship between motivating factors and cross-border online purchase intentions. Our findings help explaining consumers’ cross-border online purchasing intentions and provide guidance for retail managers and policy makers on recognizing and coping with trust and vulnerability in international relations.

Digital platforms have become a core feature of the digital economy. They facilitate the exchange of goods, services, and information, and create much social value. But at the same time, they come with harmful structural features, namely the promotion of market concentration, the rise of new forms of power imbalances, the appropriation of user data on an unprecedented scale, the facilitation of infringements of protected rights and entitlements, and the endangerment of the integrity of public discourse. While the existing legal framework has not been able to address these problems and risks adequately, the EU legislature has experienced difficulties in capturing the specific regulatory challenges caused by digital platforms so far. Now the European Commission has attained a new level in the confrontation with a double strike: the proposals for a “Digital Services Act” (DSA) and a “Digital Markets Act” (DMA) are designed to provide a coherent regulatory framework for digital platforms. This article reflects on the DMA/DSA package and provides a normative analysis of the proposals structured along the lines of market failures.

The subjection of non-signatories to arbitration agreements under the New York Convention is one of the fundamental issues of international arbitration, raising questions that touch upon the very concept of an arbitration agreement laid down in Article II. In the case of GE Energy Power Conversion v. Outokumpu, the US Supreme Court took a stand on that matter. It held that the New York Convention does not conflict with domestic law doctrines such as equitable estoppel which may bind third parties to arbitration agreements signed by others. Engaging only in an originalist interpretation of the Convention, the judgment fails to explore the normative depth of the problem.

G-protein-coupled receptors (GPCRs) are the largest superfamily of transmembrane proteins and the targets of over 30% of currently marketed pharmaceuticals. Although several structures have been solved for GPCR–G protein complexes, few are in a lipid membrane environment. Here, we report cryo-EM structures of complexes of neurotensin, neurotensin receptor 1 and Gαi1β1γ1in two conformational states, resolved to resolutions of 4.1 and 4.2 Å. The structures, determined in a lipid bilayer without any stabilizing antibodies or nanobodies, reveal an extended network of protein–protein interactions at the GPCR–G protein interface as compared to structures obtained in detergent micelles. The findings show that the lipid membrane modulates the structure and dynamics of complex formation and provide a molecular explanation for the stronger interaction between GPCRs and G proteins in lipid bilayers. We propose an allosteric mechanism for GDP release, providing new insights into the activation of G proteins for downstream signaling.

Cell death in human diseases is often a consequence of disrupted cellular homeostasis. If cell death is prevented without restoring cellular homeostasis, it may lead to a persistent dysfunctional and pathological state. Although mechanisms of cell death have been thoroughly investigated1–3, it remains unclear how homeostasis can be restored after inhibition of cell death. Here we identify TRADD4–6, an adaptor protein, as a direct regulator of both cellular homeostasis and apoptosis. TRADD modulates cellular homeostasis by inhibiting K63-linked ubiquitination of beclin 1 mediated by TRAF2, cIAP1 and cIAP2, thereby reducing autophagy. TRADD deficiency inhibits RIPK1-dependent extrinsic apoptosis and proteasomal stress-induced intrinsic apoptosis. We also show that the small molecules ICCB-19 and Apt-1 bind to a pocket on the N-terminal TRAF2-binding domain of TRADD (TRADD-N), which interacts with the C-terminal domain (TRADD-C) and TRAF2 to modulate the ubiquitination of RIPK1 and beclin 1. Inhibition of TRADD by ICCB-19 or Apt-1 blocks apoptosis and restores cellular homeostasis by activating autophagy in cells with accumulated mutant tau, α-synuclein, or huntingtin. Treatment with Apt-1 restored proteostasis and inhibited cell death in a mouse model of proteinopathy induced by mutant tau(P301S). We conclude that pharmacological targeting of TRADD may represent a promising strategy for inhibiting cell death and restoring homeostasis to treat human diseases.

On average, an approved drug currently costs US$2–3 billion and takes more than 10 years to develop1. In part, this is due to expensive and time-consuming wet-laboratory experiments, poor initial hit compounds and the high attrition rates in the (pre-)clinical phases. Structure-based virtual screening has the potential to mitigate these problems. With structure-based virtual screening, the quality of the hits improves with the number of compounds screened2. However, despite the fact that large databases of compounds exist, the ability to carry out large-scale structure-based virtual screening on computer clusters in an accessible, efficient and flexible manner has remained difficult. Here we describe VirtualFlow, a highly automated and versatile open-source platform with perfect scaling behaviour that is able to prepare and efficiently screen ultra-large libraries of compounds. VirtualFlow is able to use a variety of the most powerful docking programs. Using VirtualFlow, we prepared one of the largest and freely available ready-to-dock ligand libraries, with more than 1.4 billion commercially available molecules. To demonstrate the power of VirtualFlow, we screened more than 1 billion compounds and identified a set of structurally diverse molecules that bind to KEAP1 with submicromolar affinity. One of the lead inhibitors (iKeap1) engages KEAP1 with nanomolar affinity (dissociation constant (Kd) = 114 nM) and disrupts the interaction between KEAP1 and the transcription factor NRF2. This illustrates the potential of VirtualFlow to access vast regions of the chemical space and identify molecules that bind with high affinity to target proteins.

We employ a combination of 13C/15N magic angle spinning (MAS) NMR and 2H NMR to study the structural and functional consequences of different membrane environments on VDAC1 and, conversely, the effect of VDAC1 on the structure of the lipid bilayer. MAS spectra reveal a well-structured VDAC1 in 2D crystals of dimyristoylphosphatidylcholine (DMPC) and diphytanoylphosphatidylcholine (DPhPC), and their temperature dependence suggests that the VDAC structure does not change conformation above and below the lipid phase transition temperature. The same data show that the N-terminus remains structured at both low and high temperatures. Importantly, functional studies based on electrophysiological measurements on these same samples show fully functional channels, even without the presence of Triton X-100 that has been found necessary for in vitro-refolded channels. 2H solid-state NMR and differential scanning calorimetry were used to investigate the dynamics and phase behavior of the lipids within the VDAC1 2D crystals. 2H NMR spectra indicate that the presence of protein in DMPC results in a broad lipid phase transition that is shifted from 19 to ∼27 °C and show the existence of different lipid populations, consistent with the presence of both annular and bulk lipids in the functionally and structurally homogeneous samples.

The COVID‐19 pandemic continues to pose a substantial threat to human lives and is likely to do so for years to come. Despite the availability of vaccines, searching for efficient small‐molecule drugs that are widely available, including in low‐ and middle‐income countries, is an ongoing challenge. In this work, we report the results of an open science community effort, the “Billion molecules against COVID‐19 challenge”, to identify small‐molecule inhibitors against SARS‐CoV‐2 or relevant human receptors. Participating teams used a wide variety of computational methods to screen a minimum of 1 billion virtual molecules against 6 protein targets. Overall, 31 teams participated, and they suggested a total of 639,024 molecules, which were subsequently ranked to find ‘consensus compounds’. The organizing team coordinated with various contract research organizations (CROs) and collaborating institutions to synthesize and test 878 compounds for biological activity against proteases (Nsp5, Nsp3, TMPRSS2), nucleocapsid N, RdRP (only the Nsp12 domain), and (alpha) spike protein S. Overall, 27 compounds with weak inhibition/binding were experimentally identified by binding‐, cleavage‐, and/or viral suppression assays and are presented here. Open science approaches such as the one presented here contribute to the knowledge base of future drug discovery efforts in finding better SARS‐CoV‐2 treatments.

Atomic-level information about the structure and dynamics of biomolecules is critical for an understanding of their function. Nuclear magnetic resonance (NMR) spectroscopy provides unique insights into the dynamic nature of biomolecules and their interactions, capturing transient conformers and their features. However, relaxation-induced line broadening and signal overlap make it challenging to apply NMR spectroscopy to large biological systems. Here we took advantage of the high sensitivity and broad chemical shift range of 19F nuclei and leveraged the remarkable relaxation properties of the aromatic 19F-13C spin pair to disperse 19F resonances in a two-dimensional transverse relaxation-optimized spectroscopy spectrum. We demonstrate the application of 19F-13C transverse relaxation-optimized spectroscopy to investigate proteins and nucleic acids. This experiment expands the scope of 19F NMR in the study of the structure, dynamics, and function of large and complex biological systems and provides a powerful background-free NMR probe.

Here we present a modular method for manufacturing large-sized nanodiscs using DNA-origami barrels as scaffolding corrals. Large-sized nanodiscs can be produced by first decorating the inside of DNA barrels with small lipid-bilayer nanodiscs, which open up when adding extra lipid to form large nanodiscs of diameters ∼45 or ∼70 nm as prescribed by the enclosing barrel dimension. Densely packed membrane protein arrays are then reconstituted within these large nanodiscs for potential structure determination. Furthermore, we demonstrate the potential of these nanodiscs as model membranes to study poliovirus entry.

Suitable membrane mimetics are crucial to the performance of structural and functional studies of membrane proteins. Phospholipid nanodiscs (formed when a membrane scaffold protein encircles a small portion of a lipid bilayer) have native-like membrane properties. These have been used for a variety of functional studies, but structural studies by high-resolution solution-state NMR spectroscopy of membrane proteins in commonly used nanodiscs of 10-nm diameter were limited by the high molecular weight of these particles, which caused unfavorably large NMR line widths. We have recently constructed truncated versions of the membrane scaffold protein, allowing the preparation of a range of stepwise-smaller nanodiscs (6- to 8-nm diameter) to overcome this limitation. Here, we present a protocol on the assembly of phospholipid nanodiscs of various sizes for structural studies of membrane proteins with solution-state NMR spectroscopy. We describe specific isotope-labeling schemes required for working with large membrane protein systems in nanodiscs, and provide guidelines on the setup of NMR non-uniform sampling (NUS) data acquisition and high-resolution NMR spectra reconstruction. We discuss critical points and pitfalls relating to optimization of nanodiscs for NMR spectroscopy and outline a strategy for the high-resolution structure determination and positioning of isotope-labeled membrane proteins in nanodiscs using nuclear Overhauser enhancement spectroscopy (NOESY) spectroscopy, residual dipolar couplings (RDCs) and paramagnetic relaxation enhancements (PREs). Depending on the target protein of interest, nanodisc assembly and purification can be achieved within 12–24 h. Although the focus of this protocol is on protein NMR, these nanodiscs can also be used for (cryo-) electron microscopy (EM) and small-angle X-ray and neutron-scattering studies.

During eukaryotic translation initiation, eIF3 binds the solvent-accessible side of the 40S ribosome and recruits the gate-keeper protein eIF1 and eIF5 to the decoding center. This is largely mediated by the N-terminal domain (NTD) of eIF3c, which can be divided into three parts: 3c0, 3c1, and 3c2. The N-terminal part, 3c0, binds eIF5 strongly but only weakly to the ribosome-binding surface of eIF1, whereas 3c1 and 3c2 form a stoichiometric complex with eIF1. 3c1 contacts eIF1 through Arg-53 and Leu-96, while 3c2 faces 40S protein uS15/S13, to anchor eIF1 to the scanning pre-initiation complex (PIC). We propose that the 3c0:eIF1 interaction diminishes eIF1 binding to the 40S, whereas 3c0:eIF5 interaction stabilizes the scanning PIC by precluding this inhibitory interaction. Upon start codon recognition, interactions involving eIF5, and ultimately 3c0:eIF1 association, facilitate eIF1 release. Our results reveal intricate molecular interactions within the PIC, programmed for rapid scanning-arrest at the start codon.

We engineered covalently circularized nanodiscs (cNDs) which, compared with standard nanodiscs, exhibit enhanced stability, defined diameter sizes and tunable shapes. Reconstitution into cNDs enhanced the quality of nuclear magnetic resonance spectra for both VDAC-1, a β-barrel membrane protein, and the G-protein-coupled receptor NTR1, an α-helical membrane protein. In addition, we used cNDs to visualize how simple, nonenveloped viruses translocate their genomes across membranes to initiate infection.

Understanding dysregulation of the eukaryotic initiation factor 4F (eIF4F) complex across tumor types is critical to cancer treatment development. We present a protocol and accompanying R package “eIF4F.analysis”. We describe analysis of copy number status, gene abundance and stoichiometry, survival probability, expression covariation, correlating genes, mRNA/protein correlation, and protein co-expression. Using publicly available large multi-omics data, eIF4F.analysis permits computationally derived and statistically powerful inferences regarding initiation factor regulation in human cancers and clinical relevance of protein interactions within the eIF4F complex.

Many viruses bypass canonical cap-dependent translation in host cells by using internal ribosomal entry sites (IRESs) in their transcripts; IRESs hijack initiation factors for the assembly of initiation complexes. However, it is currently unknown how IRES RNAs recognize initiation factors that have no endogenous RNA binding partners; in a prominent example, the IRES of encephalomyocarditis virus (EMCV) interacts with the HEAT-1 domain of eukaryotic initiation factor 4G (eIF4G). Here we report the solution structure of the J-K region of this IRES and show that its stems are precisely organized to position protein-recognition bulges. This multisite interaction mechanism operates on an all-or-nothing principle in which all domains are required. This preorganization is accomplished by an 'adjuster module': a pentaloop motif that acts as a dual-sided docking station for base-pair receptors. Because subtle changes in the orientation abrogate protein capture, our study highlights how a viral RNA acquires affinity for a target protein.

Eukaryotic transcription activators stimulate the expression of specific sets of target genes through recruitment of co-activators such as the RNA polymerase II-interacting Mediator complex. Aberrant function of transcription activators has been implicated in several diseases. However, therapeutic targeting efforts have been hampered by a lack of detailed molecular knowledge of the mechanisms of gene activation by disease-associated transcription activators. We previously identified an activator-targeted three-helix bundle KIX domain in the human MED15 Mediator subunit that is structurally conserved in Gal11/Med15 Mediator subunits in fungi. The Gal11/Med15 KIX domain engages pleiotropic drug resistance transcription factor (Pdr1) orthologues, which are key regulators of the multidrug resistance pathway in Saccharomyces cerevisiae and in the clinically important human pathogen Candida glabrata. The prevalence of C. glabrata is rising, partly owing to its low intrinsic susceptibility to azoles, the most widely used antifungal agent. Drug-resistant clinical isolates of C. glabrata most commonly contain point mutations in Pdr1 that render it constitutively active, suggesting that this transcriptional activation pathway represents a linchpin in C. glabrata multidrug resistance. Here we perform sequential biochemical and in vivo high-throughput screens to identify small-molecule inhibitors of the interaction of the C. glabrata Pdr1 activation domain with the C. glabrata Gal11A KIX domain. The lead compound (iKIX1) inhibits Pdr1-dependent gene activation and re-sensitizes drug-resistant C. glabrata to azole antifungals in vitro and in animal models for disseminated and urinary tract C. glabrata infection. Determining the NMR structure of the C. glabrata Gal11A KIX domain provides a detailed understanding of the molecular mechanism of Pdr1 gene activation and multidrug resistance inhibition by iKIX1. We have demonstrated the feasibility of small-molecule targeting of a transcription factor-binding site in Mediator as a novel therapeutic strategy in fungal infectious disease.

Nanodiscs constitute a tool for the solubilization of membrane proteins in a lipid bilayer, thus offering a near-native membrane environment. Many membrane proteins interact with other membrane proteins; however, the co-reconstitution of multiple membrane proteins in a single nanodisc is a random process that is adversely affected by several factors, including protein aggregation. Here, we present an approach for the controlled co-reconstitution of multiple membrane proteins in a single nanodisc. The temporary attachment of designated oligonucleotides to individual membrane proteins enables the formation of stable, detergent-solubilized membrane protein complexes by base-pairing of complementary oligonucleotide sequences, thus facilitating the insertion of the membrane protein complex into nanodiscs with defined stoichiometry and composition. As a proof of principle, nanodiscs containing a heterodimeric and heterotrimeric membrane protein complex were reconstituted using a fluorescently labeled voltage-gated anion channel (VDAC) as a model system.

The liability regime for officers and directors of German companies combines strict and lenient elements. Officers and directors are liable for simple negligence, they bear the burden of proof for establishing diligent conduct, and they are liable for unlimited damages. These elements are worrisome for the reason that managers are confronted with the full downside risk of the enterprise even though they do not internalize the benefits of the corporate venture. This overly strict regime is balanced by other features of the regime, namely comprehensive insurance and systematic under-enforcement. Even though the authority to enforce claims against the management is divided between three different actors - the supervisory board, the shareholders assembly, and individual shareholders - enforcement has remained the exception. Furthermore, under the current system of Directors’ and Officers’ (D&O) liability insurance, board members do not feel the bite of liability as they are protected by an insurance cover that is contracted and paid for by the corporation. Thus, the current German system may combine the worst of two worlds, i.e., the threat of personal liability for excessively high amounts of damages in exceptional cases, and the practical irrelevance of the liability regime in run-of-the-mill cases. The present Article analyzes the shortcomings of the present regime and submits proposals for reform.