- A: a+b two layers
- X: ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase-like
- H: ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase
- T: ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase
- F: HATPase_c_5