Interaction between phage BFK20 helicase gp41 and its host Brevibacterium flavum primase DnaG

Protein-protein interactions have been identified between the replication proteins of corynephage BFK20 and its host Brevibacterium flavum CCM 251. We tested the interactions between phage proteins gp40, gp41, gp42, gp43 and gp44 and between these phage proteins and host replication proteins DnaZX, DnaN, Dnaδ, DnaG, DnaA, RecF, TrxC, TrxB1 and SSB using a bacterial two-hybrid system. Phage proteins gp41, gp42 and gp43 self-associated, demonstrating that these proteins are oligomers in vivo. Interactions were also detected between phage protein gp41 and host proteins DnaZX, DnaN, Dnaδ, DnaG and SSB. β-galactosidase activity measurements showed that the strongest interaction was between gp41 and DnaG. The interaction was studied further using 2-dimensional blue native SDS-polyacrylamide gel electrophoresis and Western blot analysis.