Deciphering the adsorption machinery of Deep-Blue and Vp4, two myophages targeting members of the <i>Bacillus cereus</i> group

The <i>Bacillus cereus</i> group comprises closely related species, including some with pathogenic potential (e.g., <i>Bacillus anthracis</i> and <i>Bacillus cytotoxicus</i>). Their toxins represent the most frequently reported cause of food poisoning outbreaks at the European level. Bacteriophage research is undergoing a remarkable renaissance for its potential in the biocontrol and detection of such pathogens. As the primary site of phage-bacteria interactions and a prerequisite for successful phage infection, adsorption is a crucial process that needs further investigation. The current knowledge about <i>B. cereus</i> phage adsorption is currently limited to siphoviruses and tectiviruses. Here, we present the first insights into the adsorption process of <i>Herelleviridae</i> Vp4 and Deep-Blue myophages preying on <i>B. cereus</i> hosts, highlighting the importance of polysaccharide moieties in this process and confirming the binding to the host surface of Deep-Blue Gp185 and Vp4 Gp112 receptor-binding proteins and Gp119 baseplate wedge.