From 22 to 24 October, researchers of the MARBLES-project informed museum visitors about microbes: bacteria and fungi that live all around us. The event was organised around the Micro-day of Leiden, which is this year’s EU City of Science.

Transferring poo from healthy donors to the intestines of chronically ill people has beneficial effects on these recipients’ gut bacteria, also in the longer term. This is the conclusion of research by the Leiden University Medical Center (LUMC) and the Netherlands Donor Feces Bank (NDFB).

Collaborating and learning from other fields – that is what bioinformatician Hannah Augustijn enjoys most about doing research. During her PhD at Leiden University, she developed new ways to search within bacteria for the antibiotics of the future.

Are Weyl particles the ideal conductors? Do cells without a cell wall play a role in chronic Tuberculosis infections? Carlo Beenakker and Dennis Claessen want to answer these questions. They both received a KLEIN grant from the NWO. With these grants, NWO wants to stimulate innovative, fundamental r…

The aim of this thesis is to study cell-cell interactions and the development of an assay to explore and quantify the exchange of membrane compounds.

Two research groups involving Leiden University have been awarded a major European grant, the ERC Synergy Grant. This for research on the development of membranes that can clean water and purify medical drugs and research on the biological clock in certain bacteria.

A team of researchers at the Institute of Biology Leiden, in collaboration with scientists from Utrecht University, has discovered a novel approach to improve the production of antibiotics and enzymes in the soil bacteria Streptomycetes.

A microscope with incredible sharpness that leaves samples unharmed – Guido Stam helped develop one. During his PhD research, he combined light and electrons to study biological samples. ‘We can now measure things that simply weren’t possible before.’

A complex community of microbes develops in the infant gut shortly after birth. We call this community the infant gut microbiota. The microbiota influences the health of the infant, which makes the composition and function of the infant gut microbiota an important topic to study.

What are the genes and molecular mechanisms involved in bacteria-mediated plant drought tolerance?

In this thesis I examine how soil biotic and abiotic characteristics change and interact throughout the course of afforestation and how they subsequently impact tree performance.

‘Working in Leiden is a dream come true.’ Ákos Kovács studied in his birth country Hungary and worked in Germany, Denmark and Groningen. As professor of Microbiome Ecology at IBL, he immediately started working together with his new colleagues to make discoveries about the versatile bacterial species…

Antimicrobial drugs constitute a fundamental part of modern medicine. The global rise in antimicrobial resistance poses a major threat to global health.

The central question of this Vici proposal is to investigate if, and how actinobacteria exploit life without a cell wall.

About nine million people worldwide contract tuberculosis each year. Research into new treatment for this disease has received fresh stimulus with more efficient techniques and a new understanding of how the tuberculosis bacteria works.

The CMCB brings together microbial cell biology expertise in Leiden. It aims at optimal resonance between the groups and maximal exploitation of the available infrastructure and to develop innovative cross-boundary technology platforms.

Pathogenic bacteria are increasingly resistant to today’s antibiotics. Professor Gilles van Wezel seeks new forms of antibiotics in good bacteria that live in the soil.

Autophagy is a fundamental degradative process, maintaining cellular homeostasis and functions in host defense against intracellular pathogens, including mycobacteria and Salmonella.

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.

Promotores: Prof.dr. H.J.M. de Groot, Prof.dr. J. Matysik (Universitaet Leipzig)

The aim of this thesis was to study phage infection in Streptomyces, focused on cell wall-deficient cells. Bacteriophages (or phages in short) attach to the cell wall of bacteria after which they replicate and lyse the host cell.

Whether a microbe is beneficial or harmful to a plant can now be predicted with high accuracy thanks to bacLIFE. This bioinformatic tool with an intuitive interface makes it much easier to unlock the secrets of bacterial genomes. A group of Leiden biologists presented it in Nature Communications.

Bacteria caught red-handed, deeply frozen just as they were about to cause Lyme’s disease. Ariane Briegel is wildly enthusiastic about the wonders she observes thanks to three elements: a freezing technique, a camera-equipped microscope, and AI. ‘It’s fascinating. Every single cell is different.’

Throughout all domains of life, from bacteria and archaea to eukaryotes, genomes adopt well-organized three-dimensional structures that can change in space and time to accommodate preferred transcriptional programs for environmental adaptation, the maintenance of cellular identity and differentiation…

Can small molecule drugs restore the immune system’s ability to fight tuberculosis by boosting autophagy?

Bacteria carry countless hidden treasures in their DNA: fragments that could hold the key to new medicines. But how do you pick out the most promising ones from millions of options? ‘Look at the switches that turn genes on and off,’ says molecular biologist Gilles van Wezel.

Two consortia led by Leiden researchers have been awarded over one million euros by the Dutch Research Council and the Ministry of Health, Welfare and Sport to find solutions to antimicrobial resistance.

Vinasse is a major by-product generated by the sugarcane biofuel industry. It is a source of microbes, nutrients and organic matter and often it is recycled as fertilizer.

Polymyxins are clinically used antibiotics, discovered in mid-20th century. Once abandoned due to excessive nephrotoxicity, they are now used increasingly to address infections caused by multi-drug resistant Gram-negative bacteria.In this thesis, we describe the development and synthesis of analogues…

Bacteria have the ability to alter their morphology in order to adapt to changing environments.

Promotores: Prof.dr. H. van Veen & Prof.dr. W. de Boer (Wageningen University)

Microbial Sciences' contribution to the Host-Microbe Interactions research theme is to investigate how beneficial or disease-causing microbes associate and interact with their host.

During the Leiden Science Family Day, you can take part in various workshops. You can also watch various demonstrations. Where will you go?

Human and animal cells are very complex: very different chemical processes are going on at the same time, but they are separated from each other because the cells are divided in compartments. These compartments may also have a profound effect on the potential efficacy of therapeutics, because the drug…

Bacteria are highly complex and diverse organisms that have adapted to survive in ecological niches ranging from the most extreme to the most heterogeneous environments.

Bacteria often experience external challenges, such as changes in environmental conditions or attacks by bacteriophages.

Antibiotics are a class of medicine most people take for granted. But pathogenic bacteria are becoming more and more resistant to our antibiotics, and this poses a great challenge for future treatments. There is thus a great societal need to identify new molecules that can address new targets and be…

PhD defence

Phage therapy is a novel yet unmatured therapeutic approach in the face of the crisis of antimicrobial resistance (AMR). Dr. Tingjie Guo received a grant from the Elise Mathilde Fund and the LUF to develop innovative phage-antibiotic combination treatment strategy for combating AMR.

German scientists and NASA have developed a bacteria-killing coating for space toilets. With this coating they hope to protect astronauts in space stations from pathogens. Professor of Biological chemistry Nathaniel Martin sheds light on the discovery: 'You don't expect nasty bacteria up there, but…

Living systems scale from unicellular microbes to complex multispecies communities that constantly change over time. Within the theme Development & Disease, we enhance our fundamental understanding of development and homeostasis of living cells and systems. We analyze the normal situation and how stresses…

Identifying natural plant-associated bacteria that provide targeted inhibition of pathogens through the production of antimicrobial peptides.

Leiden was European City of Science in 2022: for a year Leiden was the capital of European science. Leiden University was a proud partner of Leiden2022.

In order to gain insight into the structure and function of the molecular complexes involved in chemotaxis, we use electron cryotomography (ECT). This technique allows us to directly study microbes in their native state at resolutions capable of visualizing individual proteins.

Vancomycin is a last-resort antibiotic for the treatment of many Gram-positive bacterial infections, while remaining inactive against Gram-negative strains.

The increasing resistance of pathogenic bacteria to antibiotics necessitates the discovery of new medicines.

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.

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.

In this thesis, I focused on studying the above- and belowground interactions of J. vulgaris from a plant-soil feedback (hereafter, PSF) perspective. I investigated the temporal variation of negative PSF and examined the effects of root-associated bacteria on plant performance and aboveground herbiv…

Antibiotic resistance, caused by widespread use of antibiotics, leads to bacterial infections that are difficult, if not impossible, to treat and is a major worldwide health concern.