Abstract In this paper, we study reversibility in sP colonies and in reaction systems. sP colony is a bio-inspired computational model formed from an environment and a finite set of agents. The current state of the environment is represented by a finite set of objects and the current state of the agent is given by a finite multiset of objects. By execution of a program from a set of programs associated with the agent, the agent can change the objects in its own state and possibly in the environment, too. Reaction systems are a bio-inspired computational model where reactants are transformed into products only if some inhibitors are not present. We define sP colonies without input influence and prove that to any reversible sP colony of such type an inverse sP colony can be constructed that performs inverse computation. In the second part of the paper, we show that the concept of a reversible reaction system and the notion of an inverse reaction system can be defined in a similar way, and partially reversible reaction systems can simulate reversible logic gates and reversible Turing machines.

In this paper we introduce and study P colonies where the environment is given as a string. These constructs, called automaton-like P colonies or APCol systems, behave like automata: during functioning, the agents change their own states and process