Figure 1. The concept of minimalism in protein design.

(a and b) Minimalist art rejects traditional representations of the natural world, such as landscapes and portraits, in favour of abstract, serial, and repetitive 3D forms. (c and d) By analogy, minimalist membrane proteins do not attempt to recreate the complex sequences and structures of natural proteins but instead provide modular biocompatible objects with some specific properties. (a) La Gioconda (‘The Mona Lisa') Leonardo Da Vinci (1452–1519) from https://en.wikipedia.org/wiki/Mona_Lisa. (b) Untitled, 1990 Donald Judd (1928–1994) © Judd Foundation/ARS, NY and DACS, London 2019. From the Tate Images Collection © Tate, London 2019. (c) Photosynthetic reaction centre from R. viridis, PDB ID 1PRC [102]. (d) Molecular model of a minimal de novo membrane protein (not to scale with (c)) adapted from ref. [82] (https://creativecommons.org/licenses/by/4.0/).