Genes such as phase integrases and the CRISPR cluster found in some A. macleodii strains are likely involved in phage interactions. Some genomic islands encode specific surface receptors recognised by phages, increasing the susceptibility to phage infections. Some components of GIs are lysogenic or defective phages; one of these widespread GIs encodes virus-derived mismatch repair and RNA chaperone genes. For example, the O-chain lipopolysaccharides of the bacteria may associate with the receptor binding proteins present on the Alterophage R8W, allowing attachment and entry. Just over a dozen Alterophages infecting A. macleodii have been characterised to date, including members of the Podoviridae and Autographiviridae.
