The hidden light of microorganisms
SUPSI Image Focus
From microbial ecology to photonics, research conducted by the SUPSI Institute of Microbiology (Microbial Ecology Sector) offers new insights into the interactions between microorganisms and the environment. This research includes the MicroPAS project and participation in the National Centre of Competence in Research (NCCR) Genesis, dedicated to the big questions about the origin of life.
The research activities of the Institute of Microbiology, with its five sectors, focus particularly on the environmental dimension of the One Health approach, according to which human health cannot be considered independent of environmental and animal health, but is in fact closely dependent on it.
One of the most obvious causes of environmental change affecting humans and animals is global warming. In our latitudes, favorable climatic conditions could lead to the indigenous spread of exotic infectious agents (such as the Dengue virus), which were previously only found in clinical cases from specific risk areas.
But global warming does not only act at a geographical level, it also has an impact at more subtle levels. We are in the field of microbial ecology, which studies the relationships between microbial communities and their surrounding environments, providing data on many fronts. This is the direction we need to look in to understand the work of Nicola Storelli, Head of the Microbial Ecology sector at the Institute of Microbiology (Department of Environment, Construction and Design, SUPSI), and the Microbial Photonics Across Scales (MicroPas) project conducted in collaboration with Anupam Sengupta, Professor at the University of Luxembourg.
Specifically, the MicroPAS project studies how certain phototrophic sulfur bacteria, organisms that use light as a source of energy, do not limit themselves to its metabolic use but are able to physically manipulate it within cells. These microorganisms contain intracellular sulfur globules with optical properties, potentially capable of deflecting, confining, or guiding light.
One of the most obvious causes of environmental change affecting humans and animals is global warming. In our latitudes, favorable climatic conditions could lead to the indigenous spread of exotic infectious agents (such as the Dengue virus), which were previously only found in clinical cases from specific risk areas.
But global warming does not only act at a geographical level, it also has an impact at more subtle levels. We are in the field of microbial ecology, which studies the relationships between microbial communities and their surrounding environments, providing data on many fronts. This is the direction we need to look in to understand the work of Nicola Storelli, Head of the Microbial Ecology sector at the Institute of Microbiology (Department of Environment, Construction and Design, SUPSI), and the Microbial Photonics Across Scales (MicroPas) project conducted in collaboration with Anupam Sengupta, Professor at the University of Luxembourg.
Specifically, the MicroPAS project studies how certain phototrophic sulfur bacteria, organisms that use light as a source of energy, do not limit themselves to its metabolic use but are able to physically manipulate it within cells. These microorganisms contain intracellular sulfur globules with optical properties, potentially capable of deflecting, confining, or guiding light.
SUPSI Image Focus
Chromatium okenii observed under a microscope: inside the cells, sulfur globules can be seen “glowing,” intracellular structures with optical properties that are the focus of the MicroPAS project on living photonic materials.
To understand how this regulatory mechanism works, mathematical models and techniques are used to analyze the composition of sulfur granules, their distribution, and the shape of cells. There are many open questions, including how does the behavior of individual bacteria change depending on the environment? And what happens when thousands of cells act together, organizing themselves collectively?
Nicola Storelli explains that MicroPAS, thanks to the collaboration with Anupam Sengupta, proposes a new vision of microorganisms as living photonic materials, paving the way for future biological optical circuits. “The aim of the study is to demonstrate that microorganisms not only adapt to their surrounding environment, but are also capable of modifying it to improve their chances of survival. On a collective scale, groups of cells could even self-regulate the propagation of light, generating emerging effects typical of complex photonic systems.”
The project draws on recent work conducted in various biological contexts. One of these is Lake Cadagno, in Val di Piora, a veritable open-air laboratory whose stratified, sulfur-rich waters have been the subject of study for years by the SUPSI Institute of Microbiology, which is based there.
Nicola Storelli explains that MicroPAS, thanks to the collaboration with Anupam Sengupta, proposes a new vision of microorganisms as living photonic materials, paving the way for future biological optical circuits. “The aim of the study is to demonstrate that microorganisms not only adapt to their surrounding environment, but are also capable of modifying it to improve their chances of survival. On a collective scale, groups of cells could even self-regulate the propagation of light, generating emerging effects typical of complex photonic systems.”
The project draws on recent work conducted in various biological contexts. One of these is Lake Cadagno, in Val di Piora, a veritable open-air laboratory whose stratified, sulfur-rich waters have been the subject of study for years by the SUPSI Institute of Microbiology, which is based there.
SUPSI Image Focus
Lake Cadagno.
In MicroPas, the SUPSI team's task is to study Chromatium okenii, one of the main phototrophic bacteria living in the anoxic (oxygen-depleted or almost oxygen-depleted) waters of Lake Cadagno. The aim is to focus primarily on intracellular sulfur globules, structures that exhibit previously undescribed photonic properties. “Through laboratory and lake analysis,” explains Nicola Storelli, "we will evaluate how these globules modulate light, influencing the growth, motility, and ecological strategy of C. okenii, in relation to other phototrophic sulphobacteria in the chemocline (the stratified waters of the lake, whose chemical composition changes depending on depth, the typical pink band that divides the upper zone from the lower oxygen-depleted zone). Thanks to SUPSI's long experience in anoxic aquatic systems, we will link these photonic properties to the eco-physiological importance of C. okenii and its key role for the entire microbial community of the meromictic Lake Cadagno.
Recently, the expertise of the SUPSI Institute of Microbiology in the field of microbial ecology has been put to use in one of the six new National Centres of Competence in Research (NCCR) promoted by the Swiss Confederation. The NRP Genesis (total budget of CHF 16 million for four years, with the possibility of renewal for another four years) aims to address, with an interdisciplinary approach, the big questions about the origin of life on Earth and the possibility of its existence in the universe, bringing together microbiology, physics, chemistry, and planetary sciences.
Within this framework, SUPSI is participating as a scientific partner in a consortium coordinated by the Swiss Federal Institute of Technology in Zurich and the University of Lausanne, making a specific contribution linked to the study of primordial microbial ecosystems and the evolutionary mechanisms that regulate interactions between microorganisms and the environment. The inclusion in the PRN Genesis, funded by the Swiss National Science Foundation, is thus a recognition of the quality and international relevance of the research conducted by the SUPSI Institute of Microbiology on the meromictic Lake Cadagno, of which the MicroPas project is one example among many, and strengthens its role within the networks of excellence in Swiss research.
Recently, the expertise of the SUPSI Institute of Microbiology in the field of microbial ecology has been put to use in one of the six new National Centres of Competence in Research (NCCR) promoted by the Swiss Confederation. The NRP Genesis (total budget of CHF 16 million for four years, with the possibility of renewal for another four years) aims to address, with an interdisciplinary approach, the big questions about the origin of life on Earth and the possibility of its existence in the universe, bringing together microbiology, physics, chemistry, and planetary sciences.
Within this framework, SUPSI is participating as a scientific partner in a consortium coordinated by the Swiss Federal Institute of Technology in Zurich and the University of Lausanne, making a specific contribution linked to the study of primordial microbial ecosystems and the evolutionary mechanisms that regulate interactions between microorganisms and the environment. The inclusion in the PRN Genesis, funded by the Swiss National Science Foundation, is thus a recognition of the quality and international relevance of the research conducted by the SUPSI Institute of Microbiology on the meromictic Lake Cadagno, of which the MicroPas project is one example among many, and strengthens its role within the networks of excellence in Swiss research.