. Author manuscript; available in PMC: 2013 Dec 1.

Published in final edited form as: Mol Microbiol. 2012 Oct 12;86(5):1144–1155. doi: 10.1111/mmi.12049

Table 1.

Metal binding affinities of BsFur WT and mutants ^a, ^b

Fur	Site 3 (Zn)		Site 2 (Zn)		Site 3 (Mn)	Site 2 (Mn)	Site 2 (Fe)
Fur	^KZn1 (×10¹⁰ M⁻¹)	^KZn2 (×10¹⁰ M⁻¹)	^KZn3 (×10⁶ M⁻¹)	^KZn4 (×10⁶ M⁻¹)	^KMn1 (×10⁴ M⁻¹)	^KMn2 (×10⁴ M⁻¹)	^KFe^d (×10⁴ M⁻¹)
WT	710 ± 250	5.4 ± 1.0	200 ± 40	0.69 ± 0.08	620 ± 40	4.2 ± 0.4	120 ± 10
H37A (site 2)	510 ± 210	34 ± 7	3.5 ± 0.2	3.5 ± 0.2	230 ± 20	0.13 ± 0.04	0.6
H95A (site 2)	1300 ± 900	2.3± 0.8	190 ± 30	3.3 ± 0.2	250 ± 30	n.d. ^c	n.d.
H97A (site 2)	300 ± 40	11 ± 1	0.67± 0.08	0.1	110 ± 10	n.d.	n.d.
H96A (site 3)	51 ± 4	6.4± 0.8	15000 ± 3000	2.6 ± 0.2	31 ± 2	n.d.	n.d.
H132A(site3)	4.4± 0.7	0.023 ± 0.004	31 ± 2	1.8 ± 0.1	22 ± 2	5.7 ± 0.2	99 ± 20

All Zn(II) binding affinities were determined using competition assays with both Mf2 and Quin2. Representative result from multiple experiments (N≥3) is shown. Errors generated by Dynafit are shown to indicate the goodness of fit.

K_Mn1 was determined by Mf2 competition, while K_Mn2 was determined by FA-based DNA binding activation assay.

n.d.: not determined

K_Fe is determined by FA-based assay in 20 mM MOPS, pH 7.5, 0.4 M NaCl, 0.1 mM NAC.