|
Mode of Action (MoA)
|
binds and shields the Lon-protease target, phage HNH endonuclease.
|
|
Evidence
|
Dap1 was previously characterized as a partial anti-defense factor that binds directly to the phage HNH endonuclease, shielding it from Lon-mediated degradation. In this study, a PaoP5Δdap1 mutant showed reduced plaque size and phage productivity (ECO_0001038). When combined with a dap2 deletion (PaoP5Δdap1Δdap2), the phenotype was exacerbated, producing tiny plaques and ~90% empty capsids as observed by electron microscopy. One-step growth assays confirmed a severe drop in burst size (~6.68% of wild-type), and in vitro degradation assays revealed that Dap1 alone only partially protected HNH from Lon degradation. However, full protection was restored only when Dap1 and Dap2 were co-expressed, confirming that Dap1 complements Dap2’s anti-defense activity through a distinct, synergistic mechanism of physical shielding of HNH, in contrast to Dap2’s inhibition of Lon itself.
|
|
MoA Category
|
uncategorised
|
|
Subtype(s) of the defence system(s) inhibited by the protein
Defence Subtype
|
Pseudomonas aeruginosa Lon-mediated antiviral defence
|
|
Relevant publication(s)
DOI
|
10.1101/2025.03.13.642734,
10.1038/s41564-024-01719-5
|
|
Other components of the anti-defence system
Multicomponent System
|
dap2
|
|
Known structure in PDB
PDB ID
|
-
|
|
Genome(s) encoding the protein
Protein Source
|
Pseudomonas phage PaoP5
|
|
Defence system(s) inhibited by the protein
Defences
|
Lon-mediated antiviral defence
|