The Migrating Thermodynamic Quantum Hypothesis for Cytoplasmic Streaming, Sodium Pumping and other Cell Biological Phenomena, Deduced from Biofunctional Considerations of the Ultrastructure of Brush Border Microvilli

Abstract

An attempt is made to reconcile experimental data dealing with, inter alia, cytoplasmic streaming in Characean algae, contraction in actomyosin systems, Na⁺- and -K⁺ - stimulated ATPase activity and the ultrastructure of brush border microvilli. It is postulated that myosin molecules transfer energy from ATP to an actin-containing filament and that a high energy conformation is subsequently propagated along the filament. At regularly spaced intervals corresponding to the length of an actin-tropomyosin subunit, the propagation of high energy involves rejection of a pressure pulse in the direction of cytoplasmic streaming. Proteins in solution capable of storing the thermodynamic energy represented by the pressure pulse will either migrate in the opposite direction or conserve the quantized cytoplasmic flow generated by the actin-containing filaments. At sites where actin filaments are attached to the plasma membrane the high energy is propagated in another direction leading to expulsion of sodium ions and neutralization of the vectorial pressure pulse.