pTJK, a rare Mammaliicoccus lentus phage with broad-host-range, antibiofilm, and synergistic interactions with antimicrobials against resistant Staphylococcaceae.

Antimicrobial resistance in Staphylococcaceae poses a serious threat to human and animal health, driving the search for alternative strategies such as bacteriophage therapy. Here, we describe the isolation and characterization of pTJK, one of the first bacteriophages reported to infect Mammaliicoccus lentus, recovered together with its host strain TJK24 from sewage-contaminated stream water. pTJK is a novel lytic phage with a broad host range, capable of infecting multiple Mammaliicoccus and Staphylococcus species. It significantly reduced biofilm formation and disrupted preformed biofilms, including in non-host strains, and displayed synergistic activity with gentamicin and erythromycin. The phage remained viable under moderate temperature and pH variations, UV exposure, and chloroform treatment. Genome analysis revealed a 135.8 kb double-stranded DNA genome with 231 ORFs, including multiple endolysins and depolymerases potentially involved in antibiofilm activity, and no detected resistance or host virulence genes. Comparative genomics placed pTJK within the genus Sciuriunavirus, representing a novel yet-to-be-defined species. These findings highlight the rarity, genomic distinctiveness, and biotechnological potential of pTJK, reinforcing the relevance of Staphylococcaceae phages as promising tools to combat antimicrobial resistance.