7 research outputs found
Fusion‐induced growth of biomimetic polymersomes: behavior of poly(dimethylsiloxane)‐poly(ethylene oxide) vesicles in Saline Solutions Under High Agitation
Abstract Giant unilamellar vesicles serve as membrane models and primitive mockups of natural cells. With respect to the latter use, amphiphilic polymers can be used to replace phospholipids in order to introduce certain favorable properties, ultimately allowing for the creation of truly synthetic cells. These new properties also enable the employment of new preparation procedures that are incompatible with the natural amphiphiles. Whereas the growth of lipid compartments to micrometer dimensions has been well established, growth of their synthetic analogs remains underexplored. Here, the influence of experimental parameters like salt type/concentration and magnitude of agitation on the fusion of nanometer‐sized vesicles made of poly(dimethylsiloxane)‐poly(ethylene oxide) graft copolymer (PDMS‐ g ‐PEO) is investigated in detail. To this end, dynamic light scattering, microscopy, and membrane mixing assays are employed, and the process at different time and length scales is analyzed. This optimized method is used as an easy tool to obtain giant vesicles, equipped with membrane and cytosolic biomachinery, in the presence of salts at physiological concentrations
Building a community to engineer synthetic cells and organelles from the bottom-up
Employing concepts from physics, chemistry and bioengineering, 'learning-by-building' approaches are becoming increasingly popular in the life sciences, especially with researchers who are attempting to engineer cellular life from scratch. The SynCell2020/21 conference brought together researchers from different disciplines to highlight progress in this field, including areas where synthetic cells are having socioeconomic and technological impact. Conference participants also identified the challenges involved in designing, manipulating and creating synthetic cells with hierarchical organization and function. A key conclusion is the need to build an international and interdisciplinary research community through enhanced communication, resource-sharing, and educational initiatives
Effects of magnetic cobalt ferrite nanoparticles on biological and artificial lipid membranes
Transmembrane NADH Oxidation with Tetracyanoquinodimethane
The design of efficient schemes for
nicotinamide adenine dinucleotide
(NAD) regeneration is essential for the development of enzymatic biotechnological
processes in order to sustain continuous production. In line with
our motivation for the encapsulation of redox cascades in liposomes
to serve as microbioreactors, we developed a straightforward strategy
for the interfacial oxidation of entrapped NADH by ferricyanide as
an external electron acceptor. Instead of the commonly applied enzymatic
regeneration methods, we employed a hydrophobic redox shuttle embedded
in the liposome bilayer. Tetracyanoquinodimethane
(TCNQ) mediated electron transfer across the membrane and thus allowed
us to shortcut and emulate part of the electron transfer chain functionality
without the involvement of membrane proteins. To describe the experimental
system, we developed a mathematical model which allowed for the determination
of rate constants and exhibited handy predictive utility
Toward Artificial Mitochondrion: Mimicking Oxidative Phosphorylation in Polymer and Hybrid Membranes
For
energy supply to biomimetic constructs, a complex chemical
energy-driven ATP-generating artificial system was built. The system
was assembled with bottom-up detergent-mediated reconstitution of
an ATP synthase and a terminal oxidase into two types of novel nanocontainers,
built from either graft copolymer membranes or from hybrid graft copolymer/lipid
membranes. The versatility and biocompatibility of the proposed nanocontainers
was demonstrated through convenient system assembly and through high
retained activity of both membrane-embedded enzymes. In the future,
the nanocontainers might be used as a platform for the functional
reconstitution of other complex membrane proteins and could considerably
expedite the design of nanoreactors, biosensors, and artificial organelles