. 2006 Mar;188(6):2081–2095. doi: 10.1128/JB.188.6.2081-2095.2006

TABLE 5.

Summary of the effects of Fis mutations on DNA binding

Fis mutation	Fis binding site				Helix location^b
Fis mutation	fis P II^a	hin distal^a	λ attR_pd^a	λ attR_nat^a	Helix location^b
WT	++++	++++	+++	++++
N73A	++	++	++	+
Q74A	++++	++++	+++	++++	α-C
T75A	+++	+++	++	++	α-C
R76A	+++	+++	++	++	α-C
N84A	++++	++++	+	+
R85A	−	−	−	−	α-D
T87A	−	−	−	−	α-D
R89A	+	−	+	+++	α-D
K90A	−	−	−	−	α-D
K91A	+	−	−	+	α-D
K93A	+++	+++	++	+	α-D
K94A	++	+++	+++	+++	α-D
N98A	++++	++++	++++	++++

The relative DNA binding affinities are qualitatively summarized as follows: ++++, K_d_app of <4 nM; +++, K_d_app of 4 to 20 nM; ++, K_d_app of 20 to 100 nM; +, K_d_app of 100 to 1,000 nM; −, K_d_app of >1,000 nM.

α-C and α-D are the two α-helices that form the HTH motif, as shown in Fig. 2.