Business models for scholarly journals

The paper discusses progression of business models for the acquisition of scholarly journals. It starts with the subscription model which established oneself over the last decades. Based on this, package models and consortia models were developed. At the same time a business model was developed for databases calculating prices on size and access possibilities of whole institutes. Licences for e-journals took over this type of business model in order to compensate for cancelled print doublets. However, all these models do not account for the unequal usage of journals. In the future new business models have to be developed or libraries will only subscribe to cost-efficient journals in order to avoid high costs per article download.In diesem Beitrag wird die Entwicklung der Geschäftsmodelle für wissenschaftliche Zeitschriftenliteratur diskutiert. Ausgangspunkt ist das Abonnementmodell, wie es sich in den letzten Jahrzehnten herausgebildet hat. Auf diesem aufbauend wurden die Paket- und Konsortialmodelle entwickelt. Parallel dazu wurden für Datenbanken Geschäftsmodelle entwickelt, die die Preise an der Größe und den Zugriffsmöglichkeiten ganzer Institutionen orientierten. Diese Modelle wurden auf die Lizenzverträge für Zeitschriften übertragen, um den Wegfall der Mehrfachexemplare in den großen Bibliotheken zu kompensieren. Alle diese Geschäftsmodelle berücksichtigen nicht die unterschiedliche Nutzung von Zeitschriften. Um zu vermeiden, dass die Bibliotheken künftig nur noch "rentable" Zeitschriften lizenzieren, deren Kosten pro genutztem Artikel nicht zu hoch liegen, sind neue Geschäftsmodelle zu entwickeln

Identification and structural basis of C-terminal cyclic imides as natural degrons for cereblon

Cereblon (CRBN) is a ubiquitously expressed E3 ligase substrate receptor and a key player in pharmaceutical targeted protein degradation. Despite substantial insight gained into its chemical ligand space that is exploited in small-molecule protein degraders, its cellular role and native mechanism of substrate recognition remained elusive so far. In this communication, we report the discovery of C-terminal aspartimide and aminoglutarimide residues as natural degron motifs that are recognized by CRBN with high specificity. These C-terminal cyclic imides are known to form in ageing proteins as a result of spontaneous chain breaks after an attack of an asparagine or glutamine side chain amide on the adjacent peptide bond, and thereby mark potentially malfunctional protein fragments. In crystal structures, we uncover that these C-terminal cyclic imides are bound in the same fashion as small-molecule CRBN modulators, and that the residues preceding the cyclic terminus contribute to the interaction with a sequence-unspecific backbone hydrogen bonding pattern with strictly conserved residues in CRBN. We postulate that C-terminal aspartimide and aminoglutarimide residues resulting from chain breaks are largely underappreciated protein damages and represent the native degrons of CRBN