1,721,105 research outputs found
Kinetic models for autopoietic chemical systems: role of fluctuations in homeostatic regime
No full textTwo kinetic models describing the emergence of autopoietic chemical units are presented and discussed: the single reagent autopoietic mechanism (SRAM) and a reduced version (rSRAM). The proposed schemes are inspired to the autopoietic vesicles studied by Zepik et al (2001 Angew. Chem., Int. Ed. Engl. 40 199–202). Deterministic and stochastic analyses are then
performed in order to obtain conditions for growth, homeostasis and decay time behaviours of
the overall amphiphiles concentration. Only the reduced SRAM is able to exhibit all the three
regimes as experimentally observed and in order to obtain details on the time evolution of the
aggregates’ size distribution, stochastic simulations are carried out. What emerges from the
rSRAM simulation outcomes is that random fluctuations can act as selection rules for the size of the autopoietic units in the homeostatic regime suggesting how, in a prebiotic scenario,
stochastic fluctuations can select the more robust, in this case larger, as the fittest ‘organisms’
Syntetická biologie a umělá inteligence: od R.U.R. k současným výzkumným směrům
No full textLiving cells and biological mechanisms as prototypes for developing chemical artificial intelligence
No full textArtificial Intelligence (AI) is having a revolutionary impact on our societies. It is helping humans in facing the global challenges of this century. Traditionally, AI is developed in software or through neuromorphic engineering in hardware. More recently, a brand-new strategy has been proposed. It is the so-called Chemical AI (CAI), which exploits molecular, supramolecular, and systems chemistry in wetware to mimic human intelligence. In this work, two promising approaches for boosting CAI are described. One regards designing and implementing neural surrogates that can communicate through optical or chemical signals and give rise to networks for computational purposes and to develop micro/nanorobotics. The other approach concerns "bottom-up synthetic cells" that can be exploited for applications in various scenarios, including future nano-medicine. Both topics are presented at a basic level, mainly to inform the broader audience of non-specialists, and so favour the rise of interest in these frontier subjects
Approaches to semi-synthetic minimal cells: a review
No full textFollowing is a synthetic review on the minimal living cell, defined as an artificial or a semi-artificial cell having the minimal and sufficient number of components to be considered alive. We describe concepts and experiments based on these constructions, and we point out that an operational definition of minimal cell does not define a single species, but rather a broad family of interrelated cell-like structures. The relevance of these researches, considering that the minimal cell should also correspond to the early simple cell in the origin of life and early evolution, is also explained. In addition, we present detailed data in relation to minimal genome, with observations cited by several authors who agree on setting the theoretical full-fledged minimal genome to a figure between 200 and 300 genes. However, further theoretical assumptions may significantly reduce this number (i.e. by eliminating ribosomal proteins and by limiting DNA and RNA polymerases to only a few, less specific molecular species). Generally, the experimental approach to minimal cells consists in utilizing liposomes as cell models and in filling them with genes/ enzymes corresponding to minimal cellular functions. To date, a few research groups have successfully induced the expression of single proteins, such as the green fluorescence protein, inside liposomes. Here, different approaches are described and compared. Present constructs are still rather far from the minimal cell, and experimental as well as theoretical difficulties opposing further reduction of complexity are discussed. While most of these minimal cell constructions may represent relatively poor imitations of a modern full-fledged cell, further studies will begin precisely from these constructs. In conclusion, we give a brief outline of the next possible steps on the road map to the minimal cell. © Springer-Verlag 2005
Protein Synthesis in Sub-Micrometer Water-in-Oil Droplets
No full textWater-in-oil (w/o) emulsions are used as a cellular model because of their unique cell-like architecture. Previous works showed the capability of eukaryotic-cell-sized w/o droplets (550 mm) to support protein synthesis efficiently; however data about smaller w/o compartments (<1 mu m) are lacking. This work focuses on the biosynthesis of the enhanced green fluorescent protein (EGFP) inside sub-micrometric lecithin-based w/o droplets (0.8-1 mu m) and on its dependence on the compartments' dynamic properties in terms of solute exchange mechanisms. We demonstrated that protein synthesis is strongly affected by the nature of the lipid interface. These findings could be of value and interest for both basic and applied research
On the Evaluation of Observed Semantic Information in Synthetic Cells
No full textIn our previous work, we characterized how synthetic cells extract 'stored' semantic information from their environment. For the same scenario, we present here preliminary results on the computation of 'observed' semantic information. In contrast to stored semantic information, which refers to information exchanged between a system and its environment in its initial distribution, the observed semantic information refers to the information that is dynamically acquired by a system to maintain its own existence. Both the concepts of stored and observed semantic information were first introduced by Kolchinsky and Wolpert in 2018 to take into accounts correlations that carry "significance"or "meaning"for a given system
On the “Life-Likeness” of Synthetic Cells
No full textOne of the most exciting and rapidly expanding research area incontemporary science isthe bottom-up construction of artificial cell-like systems, also known as synthetic cells. Suchapproaches are part of the synthetic biology research paradigm, which equates to understandingmeans constructing. Accordingly, these artificial systemsare considered able to generate newknowledge based on explorative procedures that are complementary to traditional scientificinvestigations. Constructing synthetic cells aims at understanding the emergence of life fromscratch at the cellular level, modeling chemically primitive cells for unveiling origins-of-lifemysteries, and developing radically new biotechnological tools for medical, industrial, and researchapplications. The following article is dedicated to one of the most compelling open questionsemerging from the rapid improvement of synthetic cell technology: “life-likeness” of synthetic cells.Based on prior work, we promote an ‘organizational approach’ to the assessment of life-likeness,and, coherently, we propose the transition from behavioral assays, like the Turing test, to systemicstrategies, based on concepts such as organization, complexity, networks, and emergence
Trends and Outlooks in Synthetic Biology: A Special Issue for Celebrating 10 Years of <i>Life</i> and Its Landmarks
No full textSince its inception in December 2011, Board Editors, Guest Editors, as well as the Editorial Office of Life have been working hard to make Life an outstanding journal that receives the highest-quality submissions [...
- …
