- A: beta complex topology
- X: Membrane attack complex/perforin (MACPF) and cholesterol-dependent cytolysin (CDC) domains
- H: Membrane attack complex/perforin (MACPF) and cholesterol-dependent cytolysin (CDC) domains
- T: Membrane attack complex/perforin (MACPF) and cholesterol-dependent cytolysin (CDC) domains
- F: MACPF