ACER3 and infection: The virulence-enhancing effects by φRSS1 infection can be explained as follows: surface-associated φRSS1 particles (or phage proteins) may change the surface nature (hydrophobicity) of host cells to generate a high local cell density, resulting in early activation of phcA, the global virulence regulator, or lack of orf13, which is absent from the φRSS1 genome (Addy et al., 2012b).