Artificial organelles

Choi H-J, Montemagno CD (2005) Artificial organelle ATP synthesis from cellular mimetic polymersomes. Nano Lett 5 2538-2542... 

Bionanoreactors From Confined Reaction Spaces to Artificial Organelles... 

Polymer assemblies have been used in the development of various reaction spaces, ranging from model nanoreactors [6,7] up to artificial organelles [4,8], either by changing the chemical nature of the polymer assembly or of the active molecules. Model bionanoreactors have provided details of the feasibility of conducting reactions in confined spaces, eifher as single enzyme mimics [6,9], or for the combination of multiple enzymes encapsulated/inserted in specific regions of vesicles [10,11], More recently, bionanoreactors have been developed for translational applications, such as detoxification of free radicals associated with oxidative stress [12], production of antibiotics [13], or polymerization in a restricted space [14],... 

A further step has been achieved by designing bionanoreactors to function as artificial organelles, because of the retention of their activity upon cellular uptake [8], Such systems, which have a high potential for therapeutic applications, are motivating further efforts to diversify the variety of artificial organelles to truly mimic natural ones, and to offer solutions for pathological conditions. In a biomimetic approach, the concept of multicompartmentalized polymersomes has been introduced for reactions between different inner compartments encapsulated in giant structures that can serve as models for simple cellular compartments [11,15]. We include a summary of requirements needed for successful applications and models or translational examples in the development of bionanoreactors. 

PEO-b-P(DEA-s-CMA) Polymersomes GOx, Hemoglobin Model for artificial organelles, biomedical applications [63]... 

Artificial organelles, mimicking natural peroxisomes have been obtained by coencapsulating enzymes acting in tandem with Cu/Zn-superoxide dismutase and LPO/CAT in PMOXA-fc-PDMS-b-PMOXA polymersomes equipped with OmpF for permeabilization of the membrane (Fig. 11.12) [8,12]. Upon ceU uptake these nontoxic, active artificial peroxisomes detoxified superoxide... 

Ben-Haim N, Broz P, Marsch S, Meier W, Hunziker P. Cell-specific integration of artificial organelles based on functionalized polymer vesicles. Nano Lett 2008 8(5) 1368-73. 

Artificial biosynthetic pathway, 1657 Artificial enzyme design, 1633 Artificial organelle, 1672 Artificial polyploidization, 197 4-Arylcoumarins, 1555 Aryl hydrocarbon receptor (AhR), 2189 Ascending mode in CPC, 2150 Ascites, 1386... 

Another bio-inspired approach is to design polymersomes as enclosed reaction compartments for the development of nanoreactors, nanodevices, or artificial organelles, in which active compounds are not only protected from the environment, but also allowed to act in situ. For such function, membrane permeability is of crucial importance, since it allows the exchange of substrates/products with the environment of the pol)maersomes. Various methods have been reported to generate polymersomes with permeable membranes (i) polymers forming intrinsically porous membranes, (ii) polymer membranes that are permeable to ions as e.g. specific oxygen species, (iii) pore formation in pH responsive polymer membranes by chemical treatment, (iv) polymer membrane permeabilization by UV-irradiation, and (v) biopores or membrane proteins inserted into polymer membranes. ... 

Polymersomes are ideal candidates for a large variety of applications, sucb as (i) drug delivery-containers, " (ii) compartments for contrast agents, (iii) nanoreactors to serve as confined nano-spaces for transport phenomena and chemical transformation, and (iv) artificial organelles or simple mimics of cells. ... 

The polymer self-assembly can be considered as a template-free approach to produce nanomaterials. In contrast, the template-assisted approaches make use of a sacrificial template, which is initially covered by a polymeric layer and afterwards removed thus yielding polymeric capsules or containers. The latter are structures, composed of a hollow core and a polymeric shell (membrane), tiiat have shown potential as dmg and vaccine carriers as weU as in applications such as gene and protein delivery, nanoreactors, and artificial organelles. 

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