Single-pass membrane protein Membranome database Undecaprenyl phosphate N,N'-diacetylbacillosamine 1-phosphate transferase AC-42 Membrane protein Arthur Christopoulos Edward Roberts (chemist) Muscarinic acetylcholine receptor M2 Carbonic anhydrase 12 Butyrylcholinesterase Acetylcholinesterase inhibitor Μ-opioid receptor IL2RA Ligand (biochemistry)