For phenomenology, the central feature of experience is a structure called intentionality, which correlates all things experienced with the mode of experience to which the experience is referenced. 2001, Lois Bloom, Erin Tinker, Ellin Kofsky Scholnick, The Intentionality Model and Language Acquisition, page 10,
PAM(Protospacer adjacent motif) sequence in a CRISPR is a 2-6 base pair DNA sequence immediately following the DNA sequence targeted by the Cas9 nuclease in the CRISPR bacterial adaptive immune system. PAM is a component of the invading virus or plasmid, but is not a component of the bacterial CRISPR locus. Cas9 will not successfully bind to or cleave the target DNA sequence if it is not followed by the PAM sequence.
CRISPR is a bacterial system that bacteria use to fight viruses. It consists of an enzyme called Cas9 and a guiding RNA. Cas9 works together in a complex with the guide RNA to be directed to the complementary sequence of a gene that is being targeted where a ds break will be generated. Target sequence must have a PAM sequence, which is just a 3 nt sequence and varies per bacteria.