title: Exploration of the spontaneous fluctuating activity of single enzyme molecules.
abstract: Single enzyme molecules display inevitable, stochastic fluctuations in their catalytic activity. In metabolism, for instance, the stochastic activity of individual enzymes is averaged out due to their high copy numbers per single cell. However, many processes inside cells rely on single enzyme activity, such as transcription, replication, translation, and histone modifications. Here we introduce the main theoretical concepts of stochastic single-enzyme activity starting from the Michaelis-Menten enzyme mechanism. Next, we discuss stochasticity of multi-substrate enzymes, of enzymes and receptors with multiple conformational states and finally, how fluctuations in receptor activity arise from fluctuations in signal concentration. This paper aims to introduce the exciting field of single-molecule enzyme kinetics and stochasticity to a wider audience of biochemists and systems biologists.
authors.affiliation: Systems Bioinformatics, Amsterdam Institute for Molecules, Medicines and Systems, VU University Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands. a.schwabe@vu.nl
authors.forename: Anne
authors.initials: A
authors.lastname: Schwabe
authors.forename: Timo R
authors.initials: TR
authors.lastname: Maarleveld
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Bruggeman
mesh_terms: D000465:Algorithms; D004798:Enzymes / Q000737:chemistry*; D007700:Kinetics; D008956:Models, Chemical; D043562:Receptors, G-Protein-Coupled / Q000737:chemistry; D015398:Signal Transduction; D013269:Stochastic Processes
chemical_list: D004798:Enzymes; D043562:Receptors, G-Protein-Coupled
keywords: Biophysics; Enzyme kinetic; Mathematical Modeling; Michaelis–Menten; Single-molecule phenomenon; Stochastic process