文摘
We discuss the fractal nature of protein folds and some mathematical apparatus to describe them. In particular, the scaling symmetry of such selfsimilar objects is described using semigroup theory. As is also shown, purely mathematical considerations may open the way toward a possible rational design of a wide class of synthetic folds of diverse chemical nature (for potential nanotechnological applications). In this regard, a special role is given to the Walsh functions and associated with them molecular constructions called Walsh copolymers.