The 9th Open European Peroxisome Meeting (OEPM) took place in Sant Feliu de Guíxols, Costa Brava, Spain at the Eden Roc Hotel, from September 26 to 28, 2024. The OEPM is a biannual meeting organised by European researchers with an interest in the biology of peroxisomes. It has a long, successful tradition, with previous meetings being held in: Leuven, Belgium (2006); Lunteren, the Netherlands (2010); Dijon, France (2012); Neuss, Germany (2014); Vienna, Austria (2016); Groningen, the Netherlands (2018); Bochum, Germany (2020, online because of the coronavirus pandemic); and Aveiro, Portugal (2022). As before, the 9th OEPM was well attended, by 104 researchers (Fig. 1) from 17 countries (Austria, Belgium, Canada, Finland, France, Germany, India, Israel, Italy, Luxembourg, the Netherlands, Poland, Portugal, Spain, Switzerland, the UK and the USA). Traditionally, the OEPM aims at giving young researchers (graduate students and junior postdoctoral researchers) the opportunity to present their work to an international audience. At the 9th OEPM, 33 oral presentations were given by early-stage researchers, distributed over eight sessions, 23 flash talks were presented, and 48 posters displayed.

a Group photo of the participants of the 9th Open European Peroxisome Meeting (OEPM) on the Eden Roc in Sant Feliu de Guíxols, Costa Brava, Spain. b Best Paper Award lecture given by Triana Amen, University of Southampton, UK (on screen). The award was handed out by the organisers Michael Schrader, University of Exeter (left) and Ralf Erdmann, University of Bochum (right) to Charlotte Howman, a student from Triana Amen’s group (University of Southampton, UK)

As in previous years, the OEPM 2024 Peroxisome Best Paper Award (sponsored by Springer Nature and Ruhr-University of Bochum) was presented during the meeting. This award is usually given to the early career researcher who was first author of the publication judged to be the best in the peroxisome field in the last 2 years. This year, owing to the unavailability of the first author, the award was given to Triana Amen, senior author on the awarded paper, who is establishing her laboratory at the University of Southampton, UK. This paper introduces novel fluorescent fatty acid conjugates for live cell imaging of peroxisomes (Korotkova et al. 2024). These new peroxisome-specific probes, PeroxiSPY650 (far red) and PeroxiSPY555 (red), combine high peroxisome specificity, bright fluorescence and fast non-cytotoxic staining, making them valuable tools for live cell, whole organism, or tissue imaging of peroxisomes in health and disease conditions. The probes have been developed in cooperation with the company Spirochrome AG—Probes for Bioimaging, who kindly sponsored our meeting, and are now commercially available. Triana Amen presented the Young Investigator Award lecture about the publication at the end of the meeting in the Awards session. Jury members for this award were Jorge Azevedo (Porto), Johannes Berger (Vienna), Ralf Erdmann (Bochum), Marc Fransen (Leuven), Christos Gatsogiannis (Münster), Sigrun Reumann (Hamburg), Daniela Ribeiro (Aveiro), Michael Schrader (Exeter), Bettina Warscheid (Würzburg), Hans Waterham (Amsterdam) and Einat Zalckvar (Ramat-Gan).

Einat Zalckvar (Bar-Ilan University, Israel) reminded the participants about the PeroxiClub, an online platform for scientists with an interest in peroxisome research. The platform, which is maintained by Einat Zalckvar, allows researchers to communicate, exchange information and attend inspiring monthly lectures on peroxisome biology. The PeroxiClub is very well recognised and supports activities such as mouse and monoclonal antibody resources for peroxisome biology (Joseph G Hacia, University of Southern California, USA; Aamir R. Zuberi, The Jackson Laboratory, USA).

Furthermore, Einat Zalckvar (Bar-Ilan University, Israel) and Ralf Erdmann (University of Bochum, Germany) announced the upcoming first EMBO Workshop on peroxisomes entitled “Celebrating 70 Years of Peroxisome Research” taking place September 2–6, 2025 at the same location, the Hotel Eden Roc in Sant Feliu de Guixols, Costa Brava, Spain.

Peroxisomes (originally called ‘microbodies’) were discovered 70 years ago using electron microscopy (Rhodin 1954). They are intracellular organelles with a single limiting membrane surrounding a dense, proteinaceous matrix. The organelle was later named ‘peroxisome’ by Nobel Prize winner Christian De Duve (De Duve and Baudhuin 1966). Their functional characterisation revealed the presence of several H2O2-generating oxidases as well as catalase, one of the prominent peroxisomal marker enzymes, which is involved in the degradation of H2O2. Initially, the ‘Cinderella’ among the subcellular organelles gained little attention, was even considered to be a ‘fossil organelle’ and had been regarded as the cell’s ‘garbage pail’ (Schrader and Fahimi 2008). However, the peroxisome experienced a remarkable rise in interest with the discovery of its importance for cellular lipid metabolism, redox homeostasis and essential roles in human health and development.

Peroxisomes perform important metabolic functions in the β- and α-oxidation of fatty acids, the biosynthesis of ether-phospholipids (e.g. myelin sheath lipids) and polyunsaturated fatty acids such as docosahexaenoic acid with important roles in the brain and retina (Wanders et al. 2023). Peroxisomal dysfunction has been linked to different metabolic disorders (e.g. Zellweger spectrum disorders, adrenoleukodystrophy) as well as non-metabolic neurodegenerative diseases and cancer. Furthermore, peroxisomes have been associated with healthy ageing, the combat of viruses and pathogens as well as infection and immune responses (Di Cara et al. 2023).

To accomplish their functions, peroxisomes cooperate and interact with several other subcellular organelles including the ER (endoplasmic reticulum), mitochondria and lipid droplets (Silva et al. 2020). They are highly plastic and dynamic organelles that respond to environmental changes with remarkable alterations in their number, size/shape and enzyme composition. Their biogenesis depends on an increasing number of essential biogenesis factors, so called peroxins (encoded by PEX genes) which mediate matrix protein import, membrane assembly and multiplication/proliferation (reviewed in Kumar et al. 2024). The protein import machinery is rather unique, with recent advancements in cryo-electron microscopy and structural analyses helping to spark novel models and hypotheses about its molecular mechanism.

At OEPM 2024, several of these exciting topics of peroxisome biology were discussed in eight inspiring sessions, which are summarised below.