A putative GtrB-like glycosyltransferase modulates cation-dependent BCP8-2 phage infection and cell surface structure in Bacillus cereus

Bacillus cereus is a foodborne pathogen of growing concern due to its persistence and antimicrobial resistance. To identify host determinants influencing susceptibility to phage BCP8-2, a mini-Tn10 transposon mutant library of B. cereus ATCC 14579 was constructed and screened for altered phage susceptibility. A mutant (BC2012) showing partial resistance carried an insertion in BC_RS27090 (previously BC_5432), encoding a putative GtrB-like bactoprenol glycosyltransferase. Complementation restored phage sensitivity, confirming its functional involvement. Adsorption and efficiency-of-plating assays revealed significantly reduced phage binding and infectivity in the mutant, particularly under cation-rich conditions. Microscopy showed altered surface morphology with thinner, smoother cell walls. These data indicate that gtrB affects surface properties essential for cation-dependent phage adsorption and infection and provide a foundation for future studies on the role of surface glycosylation and ionic interactions in Gram-positive phage biology. ImportancePathogenic Bacillus cereus is resilient across diverse environments and produces diverse toxins linked to foodborne outbreaks. Bacteriophages provide an effective strategy to control B. cereus; however, molecular targets of phage-host interaction are poorly understood, limiting the effective phage-based control. Current study addresses this gap by identifying a putative bactoprenol glycosyltransferase (GtrB), a vital factor in phage BCP8-2 susceptibility. Data obtained highlights partial reduction of phage infection in the gtrB mutant, demonstrating that precise glycosylation is essential for effective phage binding and entry. Our findings provide significant insights for advancing phage therapy, antibiotic resistance, and B. cereus biocontrol in food and clinical settings.