Streptomyces are bacteria abundant in soil that participate in diverse and complex interactions. These bacteria are the main producers of the antibiotics we currently use in the clinic.

The soil-dwelling, filamentous bacteria of the genus Streptomyces are renowned for their production of useful secondary metabolites including antibiotics. The work described in this thesis provides new insights on the role and regulation of antibiotic production and resistance in these bacteria.

Lezing

Herstel van de natuur op uitgeputte landbouwgrond en in natuurgebieden verloopt moeizaam. ‘Bodemtransplantatie’ kan mogelijk uitkomst bieden. Dat betoogt Martijn Bezemer, hoogleraar Ecologie van Plant-Microbe-Insect interacties. Oratie op 18 december.

Muziek van een composteerbare cello, foto’s en geurtjes van schimmels en een geweven wandkleed. Het zijn een aantal voorbeelden uit Super Organism, het kunstproject van Suzette Bousema waarin je de ondergrondse schimmelwereld met al je zintuigen kunt beleven. Leids milieuwetenschapper Nadia Soudzolovskaia…

The filamentous bacteria Streptomyces are widespread inhabitants of terrestrial soils.

Elk onderdeel van de kringloop op een melkveebedrijf heeft een specifieke bacterie- en schimmelsamenstelling. Dat ontdekten de Leidse postdoc onderzoeker Sofia Gomes en haar begeleiders Nadia Soudzilovskaia en Peter van Bodegom in samenwerking met het Louis Bolk instituut en Naturalis Biodiversity Centre.…

Promotie

Promotie

Promotores: Prof.dr.G.R. de Snoo and Dr. R. Heijungs

Projecten van de afdeling Environmental Biology

A Josephson junction is a device where a thin insulating barrier or a nanostructure is placed between two superconducting leads. Such a junction is essential to superconducting qubits that store quantum information due to its anharmonic spectrum.

Gisteren verscheen er een artikel in Biznews over het watertekort in California. David Zetland, universitair docent aan het Leiden University College The Hague, gaf zijn mening over dit probleem.

Antibiotic-resistant bacteria pose a major health threat. Addressing this challenge requires among others the development of new antibacterial compounds. The research described in this thesis focuses on discovering novel antibiotics from soil bacteria, specifically Streptomyces and Paenibacillus.Despite…

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.

Heterogeneous catalyzed processes are highly significant to the chemical industry. Dissociative chemisorption (DC) of molecules on surfaces is always considered as a step with a high degree of rate control for heterogeneous catalysis.

Lezing

Vooral neerslag en bodemzuurgraad bepalen welke microben in een bepaalde habitat overleven en welke niet. Deze kennis is van belang om de biodiversiteit in stand te houden. Leidse milieukundigen werkten mee aan het onderzoek. Publicatie in Nature op 1 augustus.

Promotie

The lipid membrane is a basic structural component of all living cells. Embedded in this nanometer-thin barrier, membrane proteins shape the membrane and at the same time respond to the shape of the membrane.

The intradermal administration route is attractive for vaccine delivery, because of the highly populated antigen-presenting cells in the skin. However, the skin’s main physical barrier, the stratum corneum, prevents vaccines from entering the skin.

There is an urgent need for more physiologically relevant cell culture methods to guide compound selection in pre-clinical stages of the drug development pipeline.

Promotie

How can we quantify the density of species within a community through environmental DNA concentrations?

The book ‘Bestrijdingsmiddelen en Milieu' gives a transparent overview of facts and figures concerning pesticide use in the Netherlands and the impact of pesticides on the environment.

Supervisor: P.J.J. Hooykaas

Mycorrhizas are symbiotic associations between soil fungi and most plant species.

De afdeling Environmental Biology (CML-EB) houdt zich bezig met vraagstukken rondom biodiversiteit en natuurlijke hulpbronnen op het platteland in westerse en niet-westerse gebieden.

Food security is challenged by a growing global population and by climate change. Drought and soil salinity are considered the most important ones that inhibit crop yield and distribution. Worryingly, climate change is predicted to increase not only their frequency and severity, but also their co-occurrence,…

Promotor: G.P. van Wezel, Co-promotor: D. Claessen

The overall objectives of my thesis are to investigate the dynamics of the sorghum root microbiome and to explore the beneficial effects of the root microbiome on sorghum growth and stress tolerance.

Mycoheterotrophy is a particular mode of life in which plants obtain carbohydrates from their associated fungal partners, instead of by using photosynthesis.

The thesis describes terrestrial field trials aimed to detect side-effects of pesticides within the framework of pesticide registration procedures. Field trials were developed using vascular plants Brassica napus and Poa annua, caterpillars Pieris brassicae and effects on decomposition were studied…

Supervisor: P.J.J. Hooykaas Co-Supervisor: R. Offringa

Promotor: Prof.dr. G.P. van Wezel

Promotie

Promotie

Plants are colonized by an astounding number of microorganisms that can provide different life-support functions, including nutrient acquisition and protection against (a)biotic stresses like drought or pathogen attack.

Can we provide the Dutch government with an integrative framework, wherein the various policies can be placed and the need for further measures can be identified?

Creating information portals for support of European environmental policy.

The aim of this project was to estimate emissions from lead products-in-use for the past, the present and the future and assess the development of toxicological risks associated with these products.

Promotores: H.A. Udo de Haes, H.H.T. Prins, Co-promotor: H.H. de Iongh

Promotor: G.P. van Wezel, Co-Promotor: E. Vijgenboom

A management strategy has been developed for field margins to reduce pesticide drift to non-target areas and to promote biodiversity on arable land. To this end, 3 and 6 m wide strips along the edges of winter wheat, sugar beet and potato crops have been left unsprayed with herbicides and insecticides…