The dynamical contact order: protein folding rate parameters based on quantum conformational transitions

Methods for Testing the Quality Attributes of Plant-Based Foods: Meat- and Processed-Meat Analogs

The modern food system is seeing a change in consumption patterns provoked by several drivers—including ethical, health, and environmental concerns—that are increasing the sales of meat analog foods. This change is accompanied by increased research and development activities in the area of plant-based meats. The aim of the present review is to describe methods that are being employed by scientists to analyze and characterize the properties of meat alternatives and to propose standardized methods that could be utilized in the future. In particular, methods to determine the proximate composition, microstructure, appearance, textural properties, water-holding properties, cooking resilience, and sensory attributes, of plant-based meat are given. The principles behind these methods are presented, their utility is critically assessed, and practical examples will be discussed. This article will help to guide further studies and to choose appropriate methods to assess raw materials, processes, products, and consumption behavior of meat analogs.

Statistical analyses of protein folding rates from the view of quantum transition

Understanding protein folding rate is the primary key to unlock the fundamental physics underlying protein structure and its folding mechanism. Especially, the temperature dependence of the folding rate remains unsolved in the literature. Starting from the assumption that protein folding is an event of quantum transition between molecular conformations, we calculated the folding rate for all two-state proteins in a database and studied their temperature dependencies. The non-Arrhenius temperature relation for 16 proteins, whose experimental data had previously been available, was successfully interpreted by comparing the Arrhenius plot with the first-principle calculation. A statistical formula for the prediction of two-state protein folding rate was proposed based on quantum folding theory. The statistical comparisons of the folding rates for 65 two-state proteins were carried out, and the theoretical vs. experimental correlation coefficient was 0.73. Moreover, the maximum and the minimum folding rates given by the theory were consistent with the experimental results.

Protein photo-folding and quantum folding theory

The rates of protein folding with photon absorption or emission and the cross section of photon -protein inelastic scattering are calculated from quantum folding theory by use of a field-theoretical method. All protein photo-folding processes are compared with common protein folding without the interaction of photons (non-radiative folding). It is demonstrated that there exists a common factor (thermo-averaged overlap integral of the vibration wave function, TAOI) for protein folding and protein photo-folding. Based on this finding it is predicted that (i) the stimulated photo-folding rates and the photon-protein resonance Raman scattering sections show the same temperature dependence as protein folding; (ii) the spectral line of the electronic transition is broadened to a band that includes an abundant vibration spectrum without and with conformational transitions, and the width of each vibration spectral line is largely reduced. The particular form of the folding rate-temperature relation and the abundant spectral structure imply the existence of quantum tunneling between protein conformations in folding and photo-folding that demonstrates the quantum nature of the motion of the conformational-electronic system.