Promotores: G.W. Canters, T.J. Aartsma

Promotores: T. Hankemeier; R. Berger, Co-promotor: R.J. Vreeken

Can cyclic peptides provide a new generation of antibiotics?

This perspective addresses four challenges facing theorists whose aim is to make quantitatively accurate predictions for reactions of molecules on metal surfaces, and suggests ways of meeting these challenges, focusing on dissociative chemisorption reactions of H2, N2, and CH4.

Even though more than 4000 extra-solar planets are known today, only a small fraction of these has been captured in an image. To better understand the planet formation mechanisms in solar-like environments we started the Young Suns Exoplanet Survey (YSES).

In human cells, a meter-long DNA is condensed inside a micrometer-sized cell nucleus. Simultaneously, the genetic code must remain accessible for its replication and transcription to functional proteins.

MHC class I and MHC class II molecules present peptides to the immune system to drive proper T cell responses. Pharmacological modulation of T-cell responses can offer treatment options for a range of immune-related diseases.

We review the state-of-the-art in the theory of dissociative chemisorption (DC) of small gas phase molecules on metal surfaces, which is important to modeling heterogeneous catalysis for practical reasons, and for achieving an understanding of the wealth of experimental information that exists for this…

Advanced sensing techniques require graphene with high quality and well-controlled surface chemistry.

In what way can new tools and techniques be used to develop drug candidates for the treatment of neurological disorders?

Promotor: Prof.dr. E.F. van Dishoeck, Prof.dr. F.F.S. van der Tak (RUG)

N-acylethanolamines (NAEs), which include the endocannabinoid anandamide, represent an important family of signaling lipids in the brain. The lack of chemical probes that modulate NAE biosynthesis in living systems hamper the understanding of the biological role of these lipids.

The work described in this Thesis is focused on the assembly of oligosaccharide fragments derived from a fungal polysaccharide, galactosaminogalactan (GAG) and fragments of the exopolysaccharide Pel, generated by Pseudomonas aeruginosa.

Sphingolipids are important membrane compounds with a variety of functions. In mammalian cells, different enzymes are involved in the metabolism of sphingolipids, but interruption of this metabolism process leads to different diseases.

Plants produce an astonishing variety of secondary metabolites (SMs) which are thought to play vital roles in the fitness of plants through ecological interactions.

This thesis describes the design and synthesis of fragments of various cell wall carbohydrates of the Streptococcus species, including the branched Group B-specific antigen (GBC) of Group B Streptococcus, glycerol phosphate (GroP) modified group A carbohydrate (GAC), and the O-acetylated type 1 capsular…

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

A thorough understanding of the workings of the cell underly the understanding of disease at the molecular level. Revealing the principles of biochemical processes helps to identify the targets for the development of new drugs. At the Leiden Institute of Chemistry (LIC), we believe that the application…

Is it possible for sugar patterns on cells to activate the immune system to combat cancer?

This paper describes two synthetic lipid models designed to replace human stratum corneum (SC) in studies of the impact of volatile organic chemicals on the molecular organization of the skin barrier lipids.

Walsh

Promotor: E. F. van Dishoeck, Co-promotor: C. Walsh

Cellular stress response pathways are activated upon exposure to chemicals and help organisms deal with various molecular dangers (e.g. oxidative stress). When these pathways become hyper-activated an adverse response takes place and cells die, which may lead to organism-level toxicity such as drug-induced…

Research projects

Lecture

Methods for accurately computing the interaction of molecules with metal surfaces are critical to understanding and thereby improving heterogeneous catalysis.

The focus of the described research in this thesis is on the oxidative stress response (Nrf2 pathway). The aim of the research presented in this thesis is to obtain more information concerning microRNAs which are involved in the Nrf2 pathway, to determine and evaluate the application of microRNAs for…

Promotor: Jelle S. Kaastra Co-promotor: Jelle de Plaa

The ongoing increase in antimicrobial resistance combined with the low discovery of novel antibiotics is a serious threat to our health care.

How can we, together international experts, define future needs of R+D contributions for innovations in the field of risk-based management of chemicals and products in a global perspective using alternative testing strategies to minimize animal tests?

Promotores: H.S. Overkleeft, G.A. van der Marel, Co-promotor: B.I. Florea

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

Promotor: P.G.L. Klinkhamer, Co-Promotores: K. Vrieling, P.P.J. Mulder

Aim of the proposal is to develop lugdunomycin into a drug candidate able to treat infectious diseases caused by multi-drug resistant pathogens.

Science, Leiden Institute of Chemistry (LIC)

From surface science towards industrial practice using high-pressure scanning tunneling microscopy.

To construct catalysts that can produce fuels from CO2 innumerable times, we need to learn much more about how catalysis works. Irene Groot is conducting groundbreaking research into catalysis at the atomic level.

To address the fundamental questions of how life on Earth emerged and how common life may be in the Universe, it is crucial to know the chemical composition of the planet-forming material.

How to improve the method in quantifying the combined effects of metal-based chemicals?

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.

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

Tackling key challenges of Chemical Biology and Medicinal Chemistry to aid drug discovery is one of the focus areas of Leiden University. To this end, the Leiden Early Drug Discovery & Development network (LED3) was established by the Leiden Institute of Chemistry (LIC), the Institute of Biology Leiden…

The government spends millions regulating companies that work with large quantities of hazardous substances. But we don’t know whether this is making the industry safer. The number of violations and incidents remains constant. This is the conclusion of external PhD candidate Rob in ’t Veld in his dissertation.…

Leiden researchers found a way to measure the tiny forces exerted by pericytes, one of the most elusive, hard to research cell types, which occur in tiny blood vessels. Building on this fundamental science, researchers may eventually find treatments for medical conditions like ischaemia.

Vibrating carbon monoxide molecules adsorbed at the surface of a salt crystal stop moving after a few milliseconds. Scientists now discovered this is dominantly due to the emission of electromagnetic waves. The role of the chemical bond at the surface thereby appears to be less important than previously…

The goal of target discovery is to identify and validate proteins and biological pathways that are involved in the disease process. Modulating these target proteins and pathways with small molecules, therapeutic proteins or other biomolecules (e.g. mRNA) could deliver an effective and safe drug or v…

Global healthcare is on the verge of an antibiotic availability crisis as bacteria have evolved resistance to nearly all known antibacterials. Identifying new antibiotics that operate via novel modes-of-action is therefore of high priority.

We focus on natural products research, traditional medicine, ethnobotany and phytochemistry.

We have conducted a full spectral line survey of the 3-13 micron region of two massive protostars, AFGL 2591 and AFGL 2136, for the first time at high spectral resolution.

Testing chemical substances without using animals. It seems a utopia, but a European team is going to develop a way to make this a reality. The RISK-HUNT3R project, led by Leiden professor Bob van de Water, received 23 million euros from the European Commission for this purpose. The project was launched…