Agustín Mangiarotti

• PhD
• Senior Postdoctoral Researcher at German Center for Neurodegenerative Diseases

Biomolecular condensates play a central role in cellular processes by interacting with membranes driving wetting transitions and inducing mutual remodeling. While condensates are known to locally alter membrane properties such as lipid packing and hydration, it remains unclear how membrane composition and phase state in turn affect condensate affin...

Membraneless organelles, formed through liquid-liquid phase separation, are essential for cellular organization and function. One important property of these biomolecular condensates is their dielectric permittivity (or micropolarity), which influences their viscosity, structural integrity, protein conformations, and hydration levels. Since permitt...

Cell-penetrating peptides (CPPs) with a cationic-hydrophobic character are recognized as carriers for delivering various therapeutics and diagnostic agents across cell membranes and into the cells. Among the most studied CPPs, nona-arginine (R9) exhibits superior penetration compared to nona-lysine (K9), suggesting that the penetration ability depe...

Extracellular vesicles (EVs) are a diverse population of membrane structures produced and released by cells into the extracellular space for the intercellular trafficking of cargo molecules. They are implicated in various biological processes, including angiogenesis, immunomodulation, and cancer cell signaling. While much research has focused on th...

Biomolecular condensates play a pivotal role in cellular processes by interacting with membranes through wetting transitions, leading to mutual remodeling. We investigated how membrane composition, particularly lipid packing, affects condensate wetting using hyperspectral imaging and phasor analysis. Our results show that lipid packing, rather than...

Smart nanocarrier-based bioactive delivery systems are a current focus in nanomedicine for allowing and boosting diverse disease treatments. In this context, the design of hybrid lipid-polymer particles can provide structure-sensitive features for tailored, triggered, and stimuli-responsive devices. In this work, we introduce hybrid cubosomes that...

Extracellular vesicles (EVs) are a diverse population of membrane structures produced and released by cells into the extracellular space for the intercellular trafficking of cargo molecules. They are implicated in various biological processes, including angiogene-sis, immunomodulation, and cancer cell signaling. While much research has focused on t...

Interactions between membranes and biomolecular condensates can give rise to complex phenomena such as wetting transitions, mutual remodeling, and endocytosis. In this study, light‐triggered manipulation of condensate engulfment is demonstrated using giant vesicles containing photoswitchable lipids. UV irradiation increases the membrane area, which...

Biomolecular condensates are highly versatile membraneless organelles involved in a plethora of cellular processes. Recent years have witnessed growing evidence of the interaction of these droplets with membrane-bound cellular structures. Condensates’ adhesion to membranes can cause their mutual molding and regulation, and their interaction is of f...

Interactions between membranes and biomolecular condensates can give rise to complex phenomena such as wetting transitions, mutual remodeling, and endocytosis. In this study, we demonstrate a light-triggered manipulation of condensate engulfment using giant vesicles containing photoswitchable lipids. UV irradiation increases the membrane area, faci...

Endomembrane damage represents a form of stress that is detrimental for eukaryotic cells1,2. To cope with this threat, cells possess mechanisms that repair the damage and restore cellular homeostasis3–7. Endomembrane damage also results in organelle instability and the mechanisms by which cells stabilize damaged endomembranes to enable membrane rep...

E. coli biofilms consist of bacteria embedded in a self‐produced matrix mainly made of protein fibers and polysaccharides. The curli amyloid fibers found in the biofilm matrix are promising versatile building blocks to design sustainable bio‐sourced materials. To exploit this potential, it is crucial to understand i) how environmental cues during b...

Membrane wetting by biomolecular condensates recently emerged as a key phenomenon in cell biology, playing an important role in a diverse range of processes across different organisms. However, an understanding of the molecular mechanisms behind condensate formation and interaction with lipid membranes is still missing. To study this, we exploited...

Cells compartmentalize parts of their interiors into liquid-like condensates, which can be reconstituted in vitro. Although these condensates interact with membrane-bound organelles, their potential for membrane remodeling and the underlying mechanisms of such interactions are not well-understood. Here, we demonstrate that interactions between prot...

Membrane wetting by biomolecular condensates recently emerged as a critical phenomenon in cell biology, involved in a great diversity of processes across different organisms. However, understanding the molecular mechanism behind this process is still missing. Exploiting ACDAN and LAURDAN properties as nano-environmental sensors in combination with...

Microbial biofilms are multicellular communities where bacteria produce an extracellular matrix mainly consisting of proteins and polysaccharides. These biofilms not only confer resistance against external stresses (e.g. antibiotics), but their physical and chemical properties can also adapt to environmental conditions (e.g. temperature, humidity,...

Cells compartmentalize their components in liquid-like condensates, which can be reconstituted in vitro. Although these condensates interact with membrane-bound organelles, the potential of membrane remodeling and the underlying mechanisms are not well understood. Here, we demonstrate that interactions between protein condensates and membranes can...

Using LAURDAN fluorescence we observed that water dynamics measured at the interface of DOPC bilayers can be differentially regulated by the presence of crowded suspensions of different proteins (HSA, IgG, Gelatin) and PEG, under conditions where the polymers are not in direct molecular contact with the lipid interface. Specifically, we found that...

Important concepts from colloidal physical chemistry such as coacervation, phase transitions, emergent properties and ionic association, are currently emerging in the lexicon of cellular biology, prompted mostly by recent experimental observations of liquid phase coexistence in the cell cytosol. Nevertheless, from an historical point of view, the a...

The membrane translocation efficiency of cell penetrating peptides (CPPs) has been largely studied, and poly-arginines have been highlighted as particularly active CPPs, especially upon negatively charged membranes. Here we inquire about the influence of membrane mechanical properties in poly-arginine adsorption, penetration and translocation, as w...

In recent years, hopanoids, a group of pentacyclic compounds found in bacterial membranes, are in the spotlight since it was proposed that they induce order in lipid membranes in a similar way cholesterol do in eukaryotes, despite their structural differences. We studied here whether diplopterol (an abundant hopanoid) promoted similar effects on mo...

Hopanoids are pentacyclic molecules present in membranes from some bacteria, recently proposed as sterol-surrogates in these organisms. Diplopterol is an abundant hopanoid that, similar to sterols, do not self-aggregate in lamellar structures when pure, but forms monolayers at the air-water interface. Here we analyze the interfacial behavior of pur...

In model lipid membranes with phase coexistence, domain sizes distribute in a very wide range, from the nanometer (reported in vesicles and supported films) to the micrometer (observed in many model membranes). Domain growth by coalescence and Ostwald ripening is slow (minutes to hours), the domain size being correlated with the size of the capture...

For decades, it has been assumed that electrostatic long-range (micron distances) repulsions in lipid bilayers are negligible due to screening from the aqueous milieu. This concept, mostly derived from theoretical calculations, is broadly accepted in the biophysical community. Here we present experimental evidence showing that domain-domain electro...

We compared the thermodynamic behavior of supported and free-standing films of phospholipids with different chain length and showed that the change in free energy for the phase transition to a denser state was greater in free-standing than in supported membranes, with the differences being independent of the chain length. The presence of the suppor...

In membranes with phase coexistence, line tension appears as an important parameter for the determination of the amount of domains, as well as their size and their shape, thus defining the membrane texture. Different molecules have been proposed as “linactants” (i.e. molecules that reduce the line tension, thereby modulating the membrane texture)....

For the biophysical study of membranes, a variety of model systems have been used to measure the different parameters and to extract general principles concerning processes that may occur in cellular membranes. However, there are very few reports in which the results obtained with the different models have been compared. In this investigation, we q...

The surface dilational modulus -or compressibility modulus- has been previously studied for monolayers composed of pure materials, where a jump in this modulus was related with the onset of percolation as a result of the establishment of a connected structure at the molecular level. In this work, we focused on monolayers composed of two components...