Abstract A powerful idea put forward in the recent philosophy of science literature is that scientific models are best understood as instruments, tools or, more generally, artifacts. This has thus far been developed combination with traditional representational approach: accordingly, current artifactualist accounts treat tools. But artifactualism and representationalism independent views, adopt...

Certain proteins utilize the high reactivity of radicals for catalysing chemically challenging reactions. These proteins contain or form a radical and therefore named 'radical enzymes'. Radicals are introduced by enzymes themselves or by (re)activating proteins called (re)activases. The X-ray structures of radical enzymes and their (re)activases revealed some structural features of these molecu...