Model of Active Transport of Ions in Archaea Cells

Active ion transport as the basis for water movement in plants

A model of active ion transport in plant root hair cells was built and can be used to independently calculate the concentration of ions inside plant cells and the resting potential on its membrane. Using the model, the maximum height to which water can be transported in plants was calculated.

Intra- and intercellular transport of substances: Models and mechanisms

Non-equilibrium-statistical models of intracellular transport are built. The most significant features of these models are microscopic reversibility and the explicit considerations of the driving forces of the process - the ATP-ADP chemical potential difference. In this paper, water transport using contractile vacuoles, the transport and assembly of microtubules and microfilaments, the protein distribution within a cell, the transport of neurotransmitters from the synaptic cleft and the transport of substances between cells using plasmodesmata are discussed. Endocytosis and phagocytosis models are considered, and transport tasks and information transfer mechanisms inside the cell are explored. Based on an analysis of chloroplast movement, it was concluded that they have a complicated method of influencing each other in the course of their movements. The role of quantum effects in sorting and control transport mechanisms is also discussed. It is likely that quantum effects play a large role in these processes, otherwise reliable molecular recognition would be impossible, which would lead to very low intracellular transport efficiency.

Protocells and LUCA: Transport of substances from first physicochemical principles

Models of the transport of substances in protocells are considered from first physicochemical principles. Functional similarities and differences in the transport systems of archaea, cyanobacteria, E. coli, and diatoms have been analyzed. Based on the selection of the most important transport systems, a model of transport of substances through the membrane of the last universal common ancestor, LUCA, was constructed. Models of isotope separation in protocells were considered. Based on the proposed models, the difference in isotope concentrations in rocks can be predicted, which can serve as an indicator of the presence of life in the early stages of evolution. Mechanisms of energy conversion for the simplest forms of directed motion in protocells are considered. A special stage in the evolution of protocells is proposed - the minimal mobile cell.

A Model of Isotope Separation in Cells at the Early Stages of Evolution

The separation of the isotopes of certain ions can serve as an important criterion for the presence of life in the early stages of its evolution. A model of the separation of isotopes during their transport through the cell membrane is constructed. The dependence of the selection coefficient on various parameters is found. In particular, it is shown that the maximum efficiency of the transport of ions corresponds to the minimum enrichment coefficient. At the maximum enrichment, the efficiency of the transport system approaches ½. Calculated enrichment coefficients are compared with experimentally obtained values for different types of cells, and the comparison shows a qualitative agreement between these quantities.

Model of active transport of ions through diatom cell biomembrane

A model of the active transport of ions in the Cascinodiscus wailesii diatom cell is constructed taking into account the transport of H(+), Na(+), K(+), Ca(+2), NO(3)(-), Cl(-), and NH(4)(+) ions. This model allows calculating intracellular concentrations of basic ions and the biomembrane resting potential. A hierarchical algorithm "one ion--one transport system" is used in the model. The dependence of the resting potential on the extracellular concentration of potassium is plotted in terms of the model. The calculated values are in good agreement with the corresponding experimental data.