A DNA-binding protein that is part of the type III partition system presumably used to ensure correct segregation of this bacteriophage. Binds to tubC (centromere-like site) DNA upstream of its own gene in a sequence-specific fashion (consensus TTGAC); binds to multiple sites in the tubC region, probably spreading from an initial site (PubMed:22538818, PubMed:29762781). Upon binding to tubC forms flexible loops over about 1 kb of DNA that forms 2 rings, covering tubC and the promoter region. This probably shuts off transcription of the operon. DNA is both bent and untwisted by TubR (PubMed:29762781). The TubR-tubC DNA complex binds to TubZ forming large bundles and decreasing TubZ's GTPase activity (PubMed:22538818). Monomer; probably dimerizes when bound to DNA (PubMed:29762781). Binds to TubZ when associated with tubC DNA (PubMed:22538818). This bacteriophage also exists as a circular plasmid prophage in its host.