AP-APSE dpol intein: A novel family A DNA polymerase intein domain.

Inteins are "protein introns" that remove themselves from their host proteins through an autocatalytic protein-splicing. After their discovery, inteins have been quickly identified in organisms from all three kingdoms of life - eucarya, bacteria and archaea, but their distribution is sporadic. Here we report the identification and bioinformatics characterization of intein in DNA polymerase A gene of bacteriophage APSE (Acyrthosiphon pisum Secondary Endosymbiont bacteriophage) infecting the Aphid secondary endosymbionts of eukaryotic insects such as Acyrthosiphon pisum, Uroleucon rudbeckiae. The insertion site of intein within APSE family A DNA polymerase extein was identified to be dpola. Hence we propose this as a unique intein of family A DNA polymerase (dpola insertion site) and only reported intein in podoviridae family.