While many bacteria and mitochondria have polyadenylate polymerases, they also have another type of polyadenylation, performed by polynucleotide phosphorylase itself.
Aínda que moitas bacterias e as mitocondrias teñen poliadenilato polimerases, tamén teñen outro tipo de poliadenilación, realizada pola propia polinucleótido fosforilase.