Quantum Theory on Glucose Transport Across Membrane

TL;DR

This paper models glucose transport across membranes using quantum conformational transition theory, analyzing different transporter conformations, calculating transition rates, and predicting temperature dependence to deepen understanding of the process.

Contribution

It introduces a quantum mechanical framework for understanding glucose transporter conformational changes and transport kinetics, providing new insights into transmembrane transport mechanisms.

Findings

Quantum transition rates for GLUT1 conformations are calculated.

Transport times differ among GLUT1, GlcP, and XylE.

Non-Arrhenius temperature dependence of transition rates is predicted.

Abstract

After a brief review of the protein folding quantum theory and a short discussion on its experimental evidences the mechanism of glucose transport across membrane is studied from the point of quantum conformational transition. The structural variations among four kinds of conformations of the human glucose transporter GLUT1 (ligand free occluded, outward open, ligand bound occluded and inward open) are looked as the quantum transition. The comparative studies between mechanisms of uniporter (GLUT1) and symporter (XylE and GlcP) are given. The transitional rates are calculated from the fundamental theory. The monosaccharide transport kinetics is proposed. The steady state of the transporter is found and its stability is studied. The glucose (xylose) translocation rates in two directions and in different steps are compared. The mean transport time in a cycle is calculated and based on it the comparison of the transport times between GLUT1,GlcP and XylE can be drawn. The non-Arrhenius temperature dependence of the transition rate and the mean transport time is predicted. It is suggested that the direct measurement of temperature dependence is a useful tool for deeply understanding the transmembrane transport mechanism.