This paper provides an approach for a simplified representation of a problem, so called lattice protein folding, for a very small protein. In particular, they

This paper provides an approach for a simplified representation of a problem, so called lattice protein folding, for a very small protein. In particular, they find a 2D lattice fold of a 6-amino acid sequence (PSVKMA). 2D lattice fold means that every amino acid must occupy discrete Euclidean coordinates (i.e. (0,2) or (2,1)), which allows you to convert the search into optimization problem. Couple of years later (using more tricks and newer D-Wave machine), we pushed the limit to 10 amino acids on the planar grid, and generalized the approach to 3D grids as well (where we were able to obtain a lattice fold of 8 amino acid sequence) [1]. This is actually still well below what your laptop can search with some effort. On the other hand, AlphaFold2 predicts coordinates of the C-alpha atoms in the continuous space, so the predicted structure would actually be an potential direct substitute for experimental structure (similar to, i.e. a structure obtained using homology modelling). [1] https://arxiv.org/abs/1811.00713 https://arxiv.org/abs/1811.00713