Table 1. Structural dataset.

receptor	PDB ID	state	organism	receptor	PDB ID	state	organism
A2A adenosine	3EML	inactive	H. sapiens	μ-opioid	4DKL	inactive	M. musculus
	3PWH	inactive	H. sapiens		5C1M	active	M. musculus
	3REY	inactive	H. sapiens	neurotens. NTS1	4BUO	inactive	R. norvegicus
	3RFM	inactive	H. sapiens		4BV0	inactive	R. norvegicus
	3UZA	inactive	H. sapiens		4BWB	inactive	R. norvegicus
	3UZC	inactive	H. sapiens		4GRV	active (?)	R. norvegicus
	3VG9	inactive	H. sapiens		4XEE	active	R. norvegicus
	3VGA	inactive	H. sapiens		4XES	active	R. norvegicus
	4EIY	inactive	H. sapiens	rhodopsin	1F88	inactive	B. taurus
	2YDO	p. active	H. sapiens		1GZM	inactive	B. taurus
	2YDV	p. active	H. sapiens		1HZX	inactive	B. taurus
	3QAK	active	H. sapiens		1L9H	inactive	B. taurus
	4UG2	active	H. sapiens		1U19	inactive	B. taurus
	4UHR	active	H. sapiens		2G87	inactive	B. taurus
β2 adrenergic	2RH1	inactive	H. sapiens		2I35	inactive	B. taurus
	3D4S	inactive	H. sapiens		2I36	inactive	B. taurus
	3PDS	inactive	H. sapiens		2J4Y	inactive	B. taurus
	3NY8	inactive	H. sapiens		2PED	inactive	B. taurus
	3NY9	inactive	H. sapiens		3C9L	inactive	B. taurus
	3NYA	inactive	H. sapiens		3C9M	inactive	B. taurus
	3P0G	active	H. sapiens		3OAX	inactive	B. taurus
	3SN6	active	H. sapiens		2HPY	inactive	B. taurus
	4LDE	active	H. sapiens		2I37	inactive	B. taurus
	4LDL	active	H. sapiens		3CAP	active	B. taurus
	4LDO	active	H. sapiens		3PXO	active	B. taurus
	4QKX	active	H. sapiens		2X72	active	B. taurus
M2 muscarinic	3UON	inactive	H. sapiens		3DQB	active	B. taurus
	4MQS	active	H. sapiens		3PQR	active	B. taurus
	4MQT	active	H. sapiens		4A4M	active	B. taurus

List of PDB entries of the six receptors considered for the bridging score profiling.