Coherent Intramolecular Dynamics in Small Enzyme Populations

Abstract

Complex internal dynamics of conformational transformations in single enzyme molecules is essential for their catalytic function [1, 2]. Such experimental methods as time-resolved X-ray spectroscopy of protein crystals or single-molecule fluorescence microscopy [3–6] allow observation of individual enzymic turnover cycles [7, 8]. Enzymic reactions in living biological cells are confined to very small spatial volumes and this can lead to qualitative changes in the kinetics of biochemical reactions [9, 10]. It has recently been suggested that classical concepts of chemical kinetics must be revised when processes inside living cells are considered [11]. New approaches are needed to take into account interactions between protein machines of the living cell and treat the cell as a whole [12]. Investigations of complete enzymic reactions in biologically relevant nanoenviroments are now possible [13]. The studies of collective dynamics of enzyme molecules in small volumes are thus important from the perspective of molecular biology applications.