Toxic component of a type II toxin-antitoxin (TA) system. Has ssRNase activity. Upon expression in E.coli or S.cerevisiae inhibits growth in liquid culture; in S.cerevisiae its expression leads to apoptosis-like characteristics. Rapidly induces apoptosis (within 2 hours) upon microinjection into mouse fibroblasts (L929 line); pretreatment of cells with dexamethasone protects them. Probably contributes to host cell death if bacterial cell lysis occurs during host infection. Its toxic effect is neutralized by coexpression with cognate antitoxin VapB2, its RNase activity is partially inhibited in vitro by VapB2 (PubMed:22046301). Forms complexes with VapB2; probably VapC2(4):VapB2(2) in the absence of DNA, and VapC2(4):VapB2(4) in the presence of DNA. Crystallizes as heterodimers with stoichiometry VapC2(4):VapB2(4) in the presence of its probable promoter DNA. The heterodimers are in contact via alternative VapC-VapC and VapB-VapB interactions. This subunit does not contact DNA. Belongs to the PINc/VapC protein family.