The pathogenicity islands PAIs are characterized by the following: they have a guanine-cytosine content GC different from the rest of the genome, they have a constant codon which adapts to the bacterial chromosome, they are surrounded by direct repeats DR; they are associated with gene transfer RNA tRNA; and they have genes that code for mobile factors such as integrase, transposase and insertion sequence elements IS 6.
Las denominadas islas de patogenicidad PAIs se caracterizan por lo siguiente: tienen un contenido de guanina-citocina G-C diferente al resto del genoma, tienen un codón constante que se adapta al cromosoma bacteriano, están rodeadas de repeticiones directas DR, se asocian a genes de RNA de transferencia tRNA, tienen genes que codifican para factores móviles como integrasas, trasposasas y elementos de secuencias de inserción IS 6.