This thesis investigates reactive interfaces in surface science across three domains: heterogeneous catalysis, environmental nanoplastics, and two-dimensional materials.

Climate change is one of the largest challenges faced by humanity. To combat this research into alternatives to fossil fuels is ongoing. Dihydrogen is considered a good alternative fuel, since its burning only forms water.

With increasing carbon dioxide levels in the atmosphere and their detrimental effect on the global climate, modern society needs to push for more renewable energy sources. Storing widely accessible and abundant solar energy in chemical bonds in the form of molecular fuel via artificial photosynthesis…

The research aims to explore the evolutionary adaptability of enzymes and the impact of temperature on protein evolution pathways, using M. tuberculosis β-lactamase BlaC as the object of study. Enzymes inherently embody a delicate balance between activity and stability, and the acquisition of new enzymatic…

Solar energy is used by photosynthetic organisms to drive energy required cellular processes. Is absorbed by two groups of pigments, located in the LHCs.

With the energy transition toward a renewable energy supply and a CO2-neutral economy, electrification of the energy system is rising in importance, which leads to the challenge of long-term storage of renewable electricity.

Pseudomonas Aeruginosa is a Gram-negative bacterium which can form biofilms, increasing its resistance against antibiotics and the host immune system. Polysaccharides are an integral part of this biofilm, one of these polysaccharides is called Psl. PslG is a glycosidase, able to cleave this polysaccharide,…

This work describes several studies into the electroreduction of carbon dioxide (CO2RR), both regarding mechanistical aspects and catalyst stability considerations. Mechanistic insights into carbon-carbon bond formation on a silver catalyst are described in Ch 2, were we find an acetaldehyde-like surface…

Advanced UHF MRI techniques provide powerful tools for studying the zebrafish brain, an emerging model in neurological research. In this work, various MRI and localized MRS methods are optimized and employed for UHF strength for studying the zebrafish brain.

Glycoside hydrolases (glycosidases/GHs) are widely abundant enzymes in all kingdoms of life and are important biocatalysts that catalyze the hydrolysis of glycosidic linkages in oligo/polysaccharides, glycoproteins and glycolipids with tremendous efficiency

De Universiteit Leiden heeft onderzoeksinstituten gevestigd in Leiden en Den Haag.

Hydrogen fuel cells are expected to be pivotal in the energetic transition towards renewable energy sources such as solar and wind power. However, their industrial scalability is severely hindered by the high cost and degradation rate of platinum catalysts, one of their key components. Addressing this…

Microscopic insight on lipid-based nanomedicine in vivo remains limited to the perception of the knowledge that could be obtained: if we interpret only what we see, then we only believe to know. Although believing to know encapsulates an undefined amount of uncertainty in the exploration of lipid-based…

Metal complexes and 2D materials like graphene were combined to produce structures that can function as sensors.

This Thesis describes a strategy to synthesize 1,2-cis-oligosaccharides modulated by additives, such as dimethylformamide (DMF), triphenylphosphine oxide (Ph3P=O) and N-methyl(phenyl)formamide (MPF), using building blocks that carry solely benzyl type protecting groups and are therefore of uniform r…

Ice, the solid state of water, plays an important role on our planet as well as the entire universe.Despite the fact that an individual water molecule has a very simple structure, its chemical bonding in the solid phase can be surprisingly complex.

Nucleoid associated proteins maintain the architecture of the bacterial chromosome and regulate gene expression, hinting that their role as transcription factors may involve local three-dimensional chromosome re-modelling.

Drug development is a time- and resource-consuming process that starts with the discovery and validation of a (protein) target that contributes to pathogenesis or disease progression.

β-Lactamases are enzymes that can break down β-lactam substrates, such as antibiotics, preventing the use of these antibiotics for the treatment of various infectious diseases. However, some compounds, β-lactamase inhibitors, can block these enzymes allowing for possible treatments using a combination…

The role of the interfacial environment during electrochemical reactions has been increasingly valued, especially for those reactions involving protons or hydroxyl ions.

The research described in this thesis focused on the use of bioorthogonal antigens to investigate immunological processes in antigen presenting cells. Bioorthogonal antigens are antigenic proteins produced through recombinant expression in a methionine auxotrophic E. coli strain.

In most applications, electrocatalysts exhibit a large surface area to volume ratio, for example using nanoparticles.

We willen allemaal een wereld waarin individuen veilig zijn, conflicten vreedzaam worden beslecht en rekening wordt gehouden met toekomstige generaties. Juristen van de Universiteit Leiden onderzoeken in hoeverre het internationaal publiekrecht voorziet in de behoeftes van een geglobaliseerde samenleving.…

Voormalige Bestuurskunde studente van de opleiding Management van de Publieke Sector, Janis Tamsma, was op zaterdag 13 janauri jl. een van de genomineerden voor de prestigieuze LUF scriptieprijzen 2016. Zij heeft helaas niet gewonnen (de winnaar was Kaspar Pucek van de Faculteit der Geesteswetenschappen,…

Eva Lammers en Harmen Goudappel, beide master arbeidsrecht en deelnemers aan het privatissimum met als thema Doorwerking van fundamentele arbeidsrechten, hebben een van hun opdrachten omgeschreven tot een blogpost voor de Database of Business Ethics (DBBE).

Terwijl de Verenigde Staten nog altijd oorlog voert met drones en China grossiert in grootschalige cyber- en informatie operaties, leven Oekraïense en Russische soldaten in loopgraven en moeten NAVO-tanks een breekijzer vormen aan het front in de Donbas. Is oorlog door technologische ontwikkelingen…

This thesis describes the synthesis and biochemical evaluation of a variety of cyclophellitol based activity-based probes and inhibitors targeting various endo- and exo-acting retaining glycosidases. In the last two decades a variety of probes and inhibitors for (hemi)cellulose degrading enzymes have…

As a virtually inexhaustible source, solar energy plays a major role in future global energy scenarios.

Multicopper oxidase, laccase, can efficiently reduce oxygen to water and are mostly used in the enzymatic biofuel cells.

This thesis systematically studies the physicochemical properties of non-planar, propeller-shaped, polycyclic aromatic hydrocarbons. The synthesis of several so-called propellerenes is described on a gram scale, using optimized procedures aimed at using less hazardous reagents and reducing the amount…

Large parts of the research described in this Thesis aims at the development of oligopeptide-masked toxins and their in situ immunoproteasome-mediated activation.

To this day, all cyclophellitol-based inhibitors and ABPs have been close analogues of their natural substrate counterparts. As a result, these probes showed high selectivity towards their target glycosidases.

In this thesis, a system pharmacology approach, integrating metabolomics, pharmacology and chemical biology, was applied to understand and modulate the endocannabinoid system across different model systems (cells, zebrafish, mice and humans).

In order to be able to develop effective medicine and treatments to prevent or cure autoimmune diseases or cancer we need to understand the mechanisms how they arise and what drives their course.Unravelling the fundamental molecular mechanisms influencing the onset and course of diseases such as allergies,…

Glycoconjugate vaccines are composed of microbial poly- or oligosaccharides covalently linked to a carrier protein.

Al het onderzoek van de Universiteit Leiden is georganiseerd in instituten. Om recht te doen aan de veelkleurigheid van het onderzoek (en dus ook aan het onderwijs) dat daar uit voortvloeit vindt u op deze pagina’s omschrijvingen van alle Leidse instituten.

Synthetic hydrogels that mimic the natural extracellular matrix in the biophysical and biochemical cues it provides to cells are in high demand, however the cell phenotypes as they are observed in vivo in numerous cases have yet to be attained.

Voormalige cliënten en projecten

Promotor: Prof.dr. H.S. Overkleeft

Chapter 2 describes a post-synthetic methodology to introduce a fluorescent label in highly lipophilic, Pam3Cys based conjugates.

Promotor: E. Bouwman, Co-promotor: S. Bonnet

Lysosomal storage disorders (LSDs) are a group of orphan diseases characterized by lysosomal dysfunction or impaired lysosomal catabolism and affect collectively about 1 in 5000 live births.

Promotor: G.A. van der Marel, Co-promotor: J.D.C. Codée

Microbial rhodopsins are photosensitive pigments implemented in the growth and adaptation of a large population of microorganisms.

In this thesis an activity-based probe was discovered that could visualize the activity of PLAATs. With an optimized gel-based ABPP assay in hand, screening of a compound library led to the discovery of alpha-ketoamides as a hit for PLAAT3.

Promotor: Prof.dr. G.J. Kroes

Climate change is a challenge for both current and future generations. New biological resources have to be developed in order to meet the demand for energy as well as the demand for food.