Probable toxic component of a putative type VII toxin-antitoxin (TA) system, probably an RNase. Probably neutralized by cognate antitoxin AF_2432. Neutralization may be due to AMPylation by AF_2432. Homodimer, probably forms a complex with cognate antitoxin AF_2432. Modified by cognate antitoxin AF_2432; probably at least 2 successive AMPylation events occur on Tyr-97. Belongs to the HepT RNase toxin family. Truncated N-terminus.