Microalgae lipid membrane models: A computational biophysics characterization

Microalgae are photosynthetic organisms that are attracting considerable attention for their potential applications in biotechnology and environmental sciences. There is a growing interest in utilizing microalgae biomass to produce nutraceutical and pharmaceutical products. Microalgae lipid membranes play a critical role in various biological functions, being at the forefront of research in fundamental biology and applied biotechnology. Thus, computational lipid bilayer models provide a powerful toolkit for unravelling the complexities of these membranes at an atomic level, providing insights that are crucial for advancing our knowledge in both fundamental biological processes and applied biotechnological developments. The objective of the present work was to develop computational lipid bilayer models to characterize the behaviour of membranes of different microalgae species. By comparing these models, we seek to identify the key factors that contribute to membrane stability and functionality, which could be useful for optimizing microalgae-based applications, namely to assess the interaction of drugs with microalgae lipid membranes. In this way, lipid bilayer models mimicking the outer lipid membrane of five microalgae species, like freshwater Chlorella vulgaris, Chlamydomonas reinhardtii and Scenedesmus sp., and the marine Nannochloropsis sp. and Schizochytrium limacinum SR-21 were developed. A computational biophysics characterization was employed to address different membrane properties, such as area/lipid, membrane thickness, order parameters, and diffusion coefficients of the lipid molecules in the different membrane models. The developed models showed distinguished behaviours in freshwater and marine microalgae lipid membranes. Moreover, it was also observed that the lipid composition of marine microalgae results in more compact and ordered membranes. Our results highlight the importance of computational approaches in advancing membrane biophysics and provide a detailed molecular perspective on the lipid membranes of different species of freshwater and marine microalgae, providing a comprehensive basis to understand their biological roles and potential biotechnological applications.