Wiedenheft, B. et al. (2011) RNA-guided complex from a bacterial immune system enhances target recognition through seed sequence interactions. Proceedings of the National Academy of Sciences of the United States of America, 108(25), pp. 10092-10097. (doi: 10.1073/pnas.1102716108) (PMID:21536913) (PMCID:PMC3121849) Full text not currently available from Enlighten. Abstract Prokaryotes have evolved multiple versions of an RNA-guided adaptive immune system that targets foreign nucleic acids.