Table 3. The width of the "channel gate" of the active site cavity of β-CA.

β-CA structures	Tyr-88′ Oη -	Tyr-88′
	Gly-107 Cα	(Cα-Cβ-Oη)
	(Distance (Å))	(Angle (°))
Co-CA-AZM	5.68	107.8
Co-CA-SCN	4.55	111.8
Co-CA-PO4	4.50	111.2
Co-CA-IOD	4.44	111.6
Co-CA-AZI	3.84	116.3
Pp-CA	3.42	114.2
Ps-CA	3.43	113.6
Hi-CA	3.71	116.4
Ec-CA	4.10	114.7

The standard value for a Tyr (Cα-Cβ-Oη) angle is 113.95°.