A Spatially Propagating Biochemical Reaction

摘要

Unlike reactions performed in the laboratory—which use homogeneous solutions having spatially uniform concentration profiles of each reactant—reactions that occur in biological systems often involve reactants that are present in concentration gradients and can display unexpected kinetic properties. Such biological reactions can generate spatio-temporal structures that derive from the inclusion of feedback, autocatalysis, and other non-linear influences on rate. While these examples are prevalent in biology, it is still challenging to engineer such systems in the laboratory. Here, we demonstrate a reaction wherein a soluble kinase enzyme phosphorylates a peptide that is immobilized to a self-assembled monolayer (SAM) and that proceeds with a spatially organized propagation of the product. This spatial control over the reaction derives from an autocatalytic feature that operates at the boundary between the substrate and product.