Expressiveness Issues in Brane Calculi: A Survey

Brane calculi are a family of biologically inspired process calculi proposed in [L. Cardelli. Brane Calculi - Interactions of biological membranes. In Proc. Computational Methods in System Biology 2004 (CMSB 2004), LNCS 3082, Springer, 2005] for modeling the interactions of dynamically nested membranes. In [L. Cardelli. Brane Calculi - Interactions of biological membranes. In Proc. Computational Methods in System Biology 2004 (CMSB 2004), LNCS 3082, Springer, 2005] a basic calculus for membranes interactions – called Phago/Exo/Pino (PEP) – is proposed, whose primitives are inspired by endocytosis and exocytosis. An alternative basic calculus – called Mate/Bud/Drip (MBD) and inspired by membrane fusion and fission – is also outlined and shown to be encodable in Phago/Exo/Pino in [L. Cardelli. Brane Calculi - Interactions of biological membranes. In Proc. Computational Methods in System Biology 2004 (CMSB 2004), LNCS 3082, Springer, 2005]. In this paper we survey some results on the comparison of the expressivity of the PEP and the MBD calculi, w.r.t. their ability to act as computational devices.