Biology subjects

Bonfio, C.

Publications and source records attributed to Bonfio, C..

2 recordsLinked to original sources

bioRxiv2025

Lipid acyl chain length and unsaturation modulate membrane surface charge and interactions with amphiphilic DNA nanoprobes

Biological membranes actively regulate their composition to fine-tune their packing, fluidity, phase and surface charge, key properties that influence biomolecular interactions driving essential cellular pathways. While membrane surface charge is often attributed to specific lipid headgroups, the role of acyl-chain chemistry in modulating the interplay between these biophysical membrane properties remains unexplored. Here, we systematically investigate how variations in acyl chain length and saturation modulate lipid packing, fluidity, and membrane surface charge in zwitterionic lipid membranes. Using amphiphilic DNA nanoprobes as model charged biomolecules, we describe the interplay between packing, fluidity, phase and charge, identifying a packing-dependent guiding principle for membrane interactions that persists in the presence of anionic lipids. We also demonstrate that the identity and hydrophobicity of membrane anchors in nanoprobes significantly influence their binding to membranes. By integrating acyl-chain chemistry with membrane biophysical properties into design criteria for biomolecular attachment, our findings provide a mechanistic framework to engineer membrane interactions with both DNA nanoprobes and DNA-based coacervates. Beyond direct application to biomimetic platforms and synthetic cell engineering, these insights are relevant to lipid-based vaccine nanotechnologies and fundamental understandings of membrane-biomolecule interactions in living cells.

biophysics↗

bioRxiv2021

Thermal oscillations enable reshuffling of genetic material in a primitive cell cycle

Self-assembling single-chain amphiphiles available in the prebiotic environment likely played a fundamental role in the advent of primitive cell cycles. However, the instability of prebiotic fatty acid-based membranes to temperature and pH seems to suggest that primitive cells could only host prebiotically-relevant processes in a narrow range of non-fluctuating environmental conditions. Here we propose a novel primitive cell cycle driven by environmental fluctuations, which enable the generation of daughter protocells with reshuffled content. A reversible membrane-to-oil phase transition accounts for the dissolution of fatty acid-based vesicles at high temperatures, and the concomitant release of genetic content. At low temperatures, fatty acid bilayers reassemble and encapsulate reshuffled genetic material in a new cohort of protocells. Notably, we find that our disassembly/reassembly cycle drives the emergence of functional RNA-containing primitive cells from parent non-functional compartments. Thus, by exploiting the intrinsic instability of prebiotic fatty acid vesicles, our results point at an environmentally-driven tunable primitive cell cycle, which supports the release and reshuffle of protocellular genetic and membrane components, potentially leading to a new generation of protocells with superior traits. In the absence of protocellular transport machinery, the environmentally-driven disassembly/assembly cycle proposed herein would have supported genetic content reshuffling transmitted to primitive cell progeny, hinting at a potential mechanism important to initiate Darwinian evolution of early lifeforms.

biophysics↗