. Author manuscript; available in PMC: 2020 Dec 24.

Published in final edited form as: Biochemistry. 2019 Dec 11;58(51):5173–5187. doi: 10.1021/acs.biochem.9b00960

Table 2.

Summary of g-values of varying Fe–S cluster species identified in this work.

Fe–S cluster	g-values	PqqE sample^a	Reductant
[4Fe–4S]_RS	[2.040, 1.927, 1.897]	RS only	dithionite
CN-bound [4Fc–4S]_RS	[2.063, 1.957, 1.913]	RS only + K¹³C¹⁵N	dithionite
[4Fe–4S]_AuxII	[2.059, 1.940, 1.903]	AuxI/AuxII	dithionite
CN-bound [4Fe–4S]_AuxII	[2.087, 1.955, 1.941]	AuxI/AuxII + K¹³C¹⁵N	dithionite
[4Fe–4S]_AuxII with H319	[2.046, 1.935, 1.922]	AuxI/AuxII/D319H	dithionite
[4Fe–4S]_AuxII with C319	[2.042, 1.938, 1.917]	AuxI/AuxII/D319C	dithionite
[2Fe–2S]_AuxI	[2.004, 1.958, 1.904]	WT, RS/AuxI	dithionite
[4Fe–4S]_AuxI	g₁ = 2.104	WT, AuxI/AuxII, and RS/AuxI	Ti(III) citrate or Eu(II)-DTPA

The sample we employed to identify the corresponding cluster signal.