Search results for "solut"

Analysis of metabolic pathways by the growth of cells in the presence of organic solvents

1996

A new approach to the analysis of metabolic pathways involving poorly water-soluble intermediates is proposed. It relies upon the ability of the hydrophobic intermediates formed by a sequence of intracellular reactions to cross the membrane(s) and partition between aqueous and organic phases, when cells are incubated in the presence of a nonpolar and nontoxic organic solvent. As a result of this thermodynamically driven efflux of the formed intermediates from the cell, they accumulate in the organic medium in sufficient quantities for GC-MS analysis and identification. This enables direct determination of the sequence of chemical reactions involved with no requirement for the isolation of e…

Modeling of Particle Number Fluctuations in Entire Cells

2012

In a recent study we developed a method to model protein diffusion in cells [1], where special attention was given to generating from image data of the measured cell a realistic digital model cell in which protein dynamics were simulated. The method was shown to be well suited for modeling non-equilibrium situations that arise, e.g., in photobleaching experiments, and to be capable of producing more detailed information about protein motion than traditional modeling.Another experimental way to assess protein dynamics is to study fluctuations in the local protein number, as it is done, e.g., in fluorescence correlation spectroscopy (FCS), or in similar measurements that apply single-plane il…

2020

The transfer of metabolites through the mitochondrial membranes is a vital process that is highly controlled and regulated by the inner membrane. A variety of metabolites, nucleotides, and cofactors are transported across the inner mitochondrial membrane (IMM) by a superfamily of membrane transporters which are known as the mitochondrial carrier family (MCF) or the solute carrier family 25 (SLC25 protein family). In humans, the MCF has 53 members encoded by nuclear genes. Members of the SLC25 family of transporters, which is the largest group of solute carriers, are also known as mitochondrial carriers (MCs). Because MCs are nuclear-coded proteins, they must be imported into the IMM. When c…

RNA Nanostructure Molecular Imaging

2020

Atomic force and transmission electron microscopies (AFM/TEM) are powerful tools to analyze RNA-based nanostructures. While cryo-TEM analysis allows the determination of near-atomic resolution structures of large RNA complexes, this chapter intends to present how RNA nanostructures can be analyzed at room temperature on surfaces. Indeed, TEM and AFM analyses permit the conformation of a large population of individual molecular structures to be observed, providing a statistical basis for the variability of these nanostructures within the population. Nevertheless, if double-stranded DNA molecular imaging has been described extensively, only a few investigations of single-stranded DNA and RNA …

1H, 13C, and 15N NMR chemical shift assignment of the complex formed by the first EPEC EspF repeat and N-WASP GTPase binding domain

2021

AbstractLEE-encoded effector EspF (EspF) is an effector protein part of enteropathogenic Escherichia coli’s (EPEC’s) arsenal for intestinal infection. This intrinsically disordered protein contains three highly conserved repeats which together compose over half of the protein’s complete amino acid sequence. EPEC uses EspF to hijack host proteins in order to promote infection. In the attack EspF is translocated, together with other effector proteins, to host cell via type III secretion system. Inside host EspF stimulates actin polymerization by interacting with Neural Wiskott-Aldrich syndrome protein (N-WASP), a regulator in actin polymerization machinery. It is presumed that EspF acts by di…

Effect of iron chelates on oil–water interface, stabilized by milk proteins: The role of phosphate groups and pH. Prediction of iron transfer from aq…

2010

International audience; Iron incorporated into food systems induces oxidation and precipitation. The consequences are reduced bioavailability and a functional modification of other food components such as proteins. The iron-chelates such as ferrous bisglycinate represent a possibility to avoid side effects, since the iron is protected. The aim of this study is to investigate the effects of iron-chelates compounds on the properties of an oil/water interface stabilized by caseinate or β-lacotoglobulin, under environmental conditions at 20 °C. Analyses were performed using dynamic drop tensiometry during 5000 s. The aqueous bulk phase is an imidazole/acetate buffer (0.1 M), containing 0.4 × 10…

What Makes a Defender? A Multilevel Study of Individual Correlates and Classroom Norms in Explaining Defending Behaviors

2018

Abstract This study examines the interplay between individual characteristics (social status, provictim attitudes, and family messages about conflict resolution) and classroom descriptive and injun...

A continuous time tug-of-war game for parabolic $p(x,t)$-Laplace type equations

2019

We formulate a stochastic differential game in continuous time that represents the unique viscosity solution to a terminal value problem for a parabolic partial differential equation involving the normalized $p(x,t)$-Laplace operator. Our game is formulated in a way that covers the full range $1<p(x,t)<\infty$. Furthermore, we prove the uniqueness of viscosity solutions to our equation in the whole space under suitable assumptions.

Exact solution of the soft-clustered vehicle-routing problem

2020

Abstract The soft-clustered vehicle-routing problem (SoftCluVRP) extends the classical capacitated vehicle-routing problem by one additional constraint: The customers are partitioned into clusters and feasible routes must respect the soft-cluster constraint, that is, all customers of the same cluster must be served by the same vehicle. In this article, we design and analyze different branch-and-price algorithms for the exact solution of the SoftCluVRP. The algorithms differ in the way the column-generation subproblem, a variant of the shortest-path problem with resource constraints (SPPRC), is solved. The standard approach for SPPRCs is based on dynamic-programming labeling algorithms. We s…

An attraction-based cellular automaton model for generating spatiotemporal population maps in urban areas

2015

We develop a cellular automaton (CA) model to produce spatiotemporal population maps that estimate population distributions in an urban area during a random working day. The resulting population maps are at 50 m and 5 minutes spatiotemporal resolution, showing clearly how the distribution of population varies throughout a 24-hour period. The maps indicate that some areas of the city, which are sparsely populated during the night, can be densely populated during the day. The developed CA model assumes that the population transition trends follow dynamics and propagation patterns similar to a contagious disease. Thus, our model designed to change the states of each grid cell (stable or dynami…