Crystal structure of the phage-encoded N-acetyltransferase in complex with acetyl-CoA, revealing a novel dimeric arrangement

Bacteriophages employ diverse mechanisms to facilitate the proliferation of bacteriophages. The Salmonella-infecting phage SPN3US contains a putative N-acetyltransferase, which is widely found in bacteriophages. However, due to low sequence similarity to the N-acetyltransferases from bacteria and eukaryotic cells, the structure and function of phage-encoded acetyltransferases are mainly unknown. This study determines the crystal structure of the putative N-acetyltransferase of SPN3US in complex with acetyl-CoA. The crystal structure showed a novel homodimeric arrangement stabilized by exchanging the C-terminal alpha-helix within the dimer. The following biochemical analyses suggested that the phage-encoded acetyltransferase might have a very narrow substrate specificity. Further studies are required to reveal the biochemical activity, which would help elucidate the interaction between the phage and host bacteria in controlling pathogenic bacteria.

Automated summary

This study determines the crystal structure of the putative N-acetyltransferase of phage SPN3US and reveals its novel homodimeric arrangement. Further biochemical analyses demonstrate that the enzyme has a very narrow substrate specificity, highlighting the need for additional studies to elucidate its biochemical activity and the interaction between phage and host bacteria.