Table 1. g-values of the Glycyl Radical Signals in Various GRE^a.

enzyme	family	gav	gx	gy	gz	H/D exchange	reference
pyruvate formate lyase	PFL	2.0037	2.0047	2.0039	2.0025	yes	(39,58)
anaerobic ribonucleotide reductase	ARNR	2.0033	2.0043	2.0033	2.0023	no	(58−61)
benzylsuccinate synthase	BSS	2.0034*	2.0045	2.0036	2.0022	yes	(57,58,62)
N-acetylglycyl radical		2.0032	2.0045	2.0031	2.0020	no	(58,63)

^aThe values measured in X-band experiments are given as g_av, and those under very-high-field conditions (525 GHz microwave frequency at up to 20 T magnetic flux density) as g_x,y,z. An organic glycyl radical model is added for reference. *A deviating g_av value of 2.0021 was initially reported⁵⁷, which may be due to improper calibration.