Table 2 Activities of wild-type and mutant topo IV enzymes

Protein	Decatenation	Relaxation	Cleavage	Basal ParE ATPase	Topo IV+DNA, fold stimulation
Wild-type ParE	100%	100%	100%	100%	4.15
^*ParE K291Q	No activity^a	No activity^a	100%	57%	1.0
^*ParE R321Q	20–25%	20%	100%	86%	1.6
^*ParE K346Q	30%	~25%	100%	72%	1.6
^*ParE R353A	10%	10%	100%	72%	1.37
^*ParE R353Q	10%	10%	100%	200%	1.3
^*ParE K346Q/R353A	1%	<0.5%	100%	93%	1.2
^*ParE K281Q/D282A	100%	100%	100%	74%	3.67
^*ParE K313Q/E316Q	100%	>100%^b	100%	65%	8.5
ParE D269V	200%	200%	100%	270%	10
^**ParE S268A	100%	100%	100%	100%	4.0
^**ParE R396Q	50%	50%	100%	100%	1.7
^**ParE R400Q	50%	50%	100%	100%	1.4

Topoisomerase IV was reconstituted from full-length ParC and wt or mutant full-length ParE and their activities were determined as the average of three independent measurements. Single asterisk denotes complexes mutated in ParE residues that interact asymmetrically with the top strand of the DNA duplex (Fig. 2): double asterisk identifies complexes mutated in residues that interact symmetrically with the bottom DNA strand in Fig. 2
^aNo activity detectable using up to 2 µg of ParE
^bAbout twofold more active than wild type. The basal ATPase activity of wt and mutant ParE proteins was novobiocin sensitive (Supplementary Table 2)

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