The surface recognition in many biological systems is guided by the interaction of carbohydrate-specific proteins (lectins) with carbohydrate epitopes (ligands) located within the unordered glycoconjugate layer (glycocalyx) of cells. Thus, for recognition, the respective ligand has to reorient for a successful matching event. Herein, we present for the first time a model system, in which only the orientation of the ligand is altered in a controlled manner without changing the recognition quality of the ligand itself. The key for this orientational control is the embedding into an interfacial system and the use of a photoswitchable mechanical joint, such as azobenzene.

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We have recently demonstrated, by employing azobenzene glycosides, that bacterial adhesion to surfaces can be switched through reversible reorientation of the carbohydrate ligands. To investigate this phenomenon further, we have turned here to more complex—that is, multivalent—azobenzene glycoclusters. We report on the synthesis of a photosensitive trivalent cluster mannoside conjugated to an azobenzene hinge at the focal point. Molecular dynamics studies suggested that this cluster mannoside, despite the conformational flexibility of the azobenzene‐glycocluster linkage, offers the potential for reversibly changing the glycocluster's orientation on a surface. Next, the photoswitchable glycocluster was attached to human cells, and adhesion assays with type 1 fimbriated Escherichia coli bacteria were performed. They showed marked differences in bacterial adhesion, dependent on the light‐induced reorientation of the glycocluster moiety. These results further underline the importance of orientational effects in carbohydrate recognition and likewise the value of photoswitchable glycoconjugates for their study.

Background: Many students have incomplete or incorrect perceptions of science and scientists. These simplified images, mediated by media or influential agents of socialisation, result in common stereotypes. Especially for occupational choices it is important to convey an authentic image about science and scientists. Purpose: One manner to convey an authentic image and thus the aim of this study is the development and validation of scientific videos including collected activities of scientists. Program description: Professors were interviewed regarding their typical scientific activities. This was followed by the development of a questionnaire which was answered by junior scientists. Authentic scientific videos were developed and finally validated in a science lab for school-students based on qualitative and quantitative results. Sample: 92 junior scientists answered the questionnaire and eight professors and 96 students (31 girls and 65 boys; grade 10 to 13) were interviewed. Design and methods: The scientists were surveyed before the development of the videos. The RIASEC+N model was used to categorise the collected activities of scientists. Finally, students were interviewed for the video validation. Results: A number of different scientific activities of each RIASEC+N dimension could be detected, which were then integrated into four videos. The interviewed students who watched those videos successfully identified all of the activities. Conclusion:The working day of scientists contains more than stereotypical aspects and wellconsidered/planned videos are one suitable option to promote an authentic overview about science and scientists.

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