DNA and circular splicing

Abstract

Circular splicing has been very recently introduced to model a specific recombinant behaviour of circular DNA, carrying on the investigation initiated with linear splicing. In this paper we restrict ourselves to the relationship between circular regular languages and circular splicing languages. We provide partial results towards a characterization of the class of circular regular languages generated by finite circular splicing systems. We consider a class of languages X closed under conjugacy relation and with X a regular languages, called here star languages. Using automata theory and combinatorial techniques on words, we show that for a subclass of star languages the corresponding circular languages are circular (Paun) splicing languages. In particular, star languages with X being a finite set or X being a free monoid belong to this subclass.