hotocatalysis has emerged as a powerful tool for enabling challenging transformations in organic synthesis. This thesis explores the development of several photocatalytic reactions designed to form carbon-heteroatom bonds from less-functionalized precursors.

Cytotoxic T-cells (CTLs) are involved in the clearance of viruses and killing of tumor cells.

This thesis describes the use of an activity-based proteomics method to study the endocannabinoid system.

The primary goal of this research is to deepen our understanding of substrate-enzyme interactions in Glycoside hydrolases. For this purpose, Bacillus circulans xylanase (BcX) has been selected as a well-established model to examine the Michaelis complex and glycosyl-enzyme adduct.

Promotor: H.S. Overkleeft, J. Neefjes, Co-promotor: M. van der Stelt

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…

Promotores: Prof.dr. H.S. Overkleeft, Prof.dr. G.A. van der Marel

Promotor: Prof.dr. A.P. IJzerman, Co-Promotor: L.H. Heitman

A structural investigation of coiled coil peptides used as membrane fusogens, mimicing naturally occuring coiled-coil fusion proteins. Synthetic modifications have been made to alter lipid attachment, secondary structure and to insert photoactive azobenzene moieties for active control over coiled coil…

Promotor: Prof.dr. H.S. Overkleeft

Prof.dr. Geert de Snoo is per 1 maart bij de Faculteit der Wiskunde en Natuurwetenschappen benoemd tot hoogleraar Conservation Biology. De Snoo blijft hoofd van de gelijknamige afdeling van het Institute of Environmental Sciences (CML).

Freshwater and brackish water ecosystems are arguably the most vulnerable ecosystems on earth, due to concentrated human developments in and around them. The Pontocaspian (PC) region located at the border of Europe and Asia contains a variety of brackish water ecosystems and unique inhabitants, known…

Promotor: A. Kros

Carbohydrates, or sugars, are the most diverse and most abundant biomolecules known. However, the isolation of carbohydrate samples in sufficient amounts and purity is often impractical or even impossible, so the chemical synthesis of glycosides becomes relevant. The glycosylation reaction, in which…

Vitamin A or retinol is essential in embryonic development, the visual cycle and the immune system.

This thesis describes the use of bioorthogonal proteins in immunological settings. It provides an introduction towards the field of protein modification, which was used throughout the thesis for the expression of proteins containing unnatural amino acids.

Phospholipase A/acyltransferase 3 (PLAAT3) and PLAAT4 are enzymes involved in the synthesis of bioactive lipids. Despite sequential and structural similarities, the two enzymes differ in activity and specificity.

Lysosomal acid glucosylceramidase (GBA1) is a lysosomal enzyme that degrades glucolipids with its main substrate being glucosylceramide (GlcCer). Defects in the GBA1 gene lead to glycosphingolipidosis Gaucher disease (GD), in which the hydrolysis of GlcCer is impaired and therefore, it accumulates in…

This thesis focuses on the social dimensions of crane and wetland conservation in rural landscapes in Kenya, Uganda and Zimbabwe.

In this thesis, bioorthogonal chemistry is combined with correlative light-electron microscopy to selectively label and study pathogenic intracellular bacteria within the host immune cell.

Promotor: J. van der Greef; Co-promotor: E. van Wijk, M. Wang

Wetenschappers van de Universiteit Leiden hebben een doorbraak bereikt in de bestudering van de erfelijke stofwisselingsziekte van Pompe. Samen met hun Yorkse collega’s ontwierpen zij een molecuul dat zich bindt aan het enzym dat aan de basis staat van het ziekteverloop. De bevindingen zijn gepubliceerd…

Promotor: Prof.dr.ir. J.G.E.M. Fraaije, Co-promotor: A. Kros

Promotor: Prof.dr. H.P. Spaink, Co-promotor: Dr. B.E. Snaar

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.

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,…

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.

In het kader van de Honours Course ‘Crises in Biology’ die plaatsvond van 19 augustus t/m 2 september 2012 in Normandië, bezochten studenten vele geologische interessante locaties. Een van deze bijzondere plekken was de kust van Arromanches. Hier bemachtigden zij een enorm grote ammoniet die ze dinsdag…

Twee jonge excellente chemici, Jeroen Codée en Sander van Kasteren, hebben een ECHO subsidie van € 260.000 euro toegekend gekregen door de Nederlandse Organisatie voor Wetenschappelijk Onderzoek. Hiermee kunnen hun onderzoeksprojecten van start gaan.

As a non-invasive genetic method, eDNA based approaches have become an important component of ecologists' and environmental managers' toolkits for biomonitoring in conservation and an increasingly important source of ecological knowledge.

Promotores: G.R. de Snoo, W.T. de Groot, Co-promotor: C.J.M. Musters

The cannabinoid receptor type 2 (CB2R) is associated with several inflammatory diseases with an unmet medical need (e.g. Alzheimers, multiple sclerosis, reumatoid arthritis). Development of new chemical biology strategies to study this protein is essential to aid future development of drugs for these…

Streptomyces present a valuable platform for natural product discovery. Lugdunomycin is a novel angucycline-derived polyketide from Streptomyces sp QL37, with unprecedented skeleton and antimicrobial activity.

Docenten spelen een cruciale rol bij het implementeren van onderwijsvernieuwingen. Uiteindelijk hangt het succes van de implementatie af van de manier waarop docenten de vernieuwing vormgeven in hun dagelijkse lespraktijk.

Promotor: H.S. Overkleeft, Co-promotor: M. van der Stelt

Promotores: Prof.dr. F. van Lunteren, Prof.dr. F.S. Gaastra

This thesis describes the synthesis, analysis of various tetrazine bearing compounds and use in bioorthogonal chemistry.

This thesis introduces the concept of

Promotors: Prof.dr. E. Bouwman, Prof.dr. E. Drent

This thesis focuses on the synthesis, characterization and performance towards CO2 electroreduction of mono and bi-metallic particles based on p-block metals

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.

Promotor: J. van der Greef, T. Hankemeier; Co-promotor: H.A. van Wietmarschen

The power of personalized nutrition lies in being able to conduct clinical research on healthy people while capturing metabolic markers sensitive to the impact of environmental and metabolic stressors (e.g. diet, changing sex hormones and the menstrual cycle).

Hybrid zones occur where two species meet and produce offspring (hybrids). Typically, hybrids show a considerable reduction in fitness. In this thesis two hybrid zones are treated.