Table 1. Regulon downstream genes.

		S. meliloti		Outgroups
Regulator	Replicon a	Mean regulon size	MAD b	Mean regulon size	MAD b
HpdR	Chromosome	3.10	1.0	2.4	1.0
OxyR	Chromosome	1.71	0.0	0.0	0.0
NesR	Chromosome	8.24	1.0	6.0	NA
AglR	Chromosome	11.69	2.0	6.4	4.0
BetI	Chromosome	3.22	0.0	2.2	0.0
MucR	Chromosome	5.20	1.0	2.4	0.0
NtrR	Chromosome	1.57	2.0	NA	NA
ChvI	Chromosome	3.53	1.0	0.6	0.0
SMc04401	Chromosome	4.04	1.0	6.4	9.0
Fur	Chromosome	4.45	2.0	4.5	1.0
IolR	Chromosome	41.80	10.0	45.4	7.0
RirA	Chromosome	71.55	8.0	78.2	4.0
SMc03165	Chromosome	1.69	0.0	4.4	1.0
PckR	Chromosome	69.80	13.0	45.0	3.0
GlnBK	Chromosome	15.35	4.0	16.2	2.0
LsrAB1	Chromosome	2.86	2.0	3.4	3.0
NifA	pSymA	8.02	2.0	2.6	3.0
FixJ	pSymA	5.86	1.0	16.5	NA
FixK1	pSymA	24.27	6.0	16.8	5.0
RctR	pSymA	4.59	2.0	NA	NA
RhrA	pSymA	3.79	1.0	NA	NA
SyrM	pSymA	1.10	0.0	1.0	NA
NodD1	pSymA	6.77	2.0	10.0	NA
NodD2	pSymA	6.41	2.0	17.0	NA
NodD3	pSymA	6.71	2.0	6.4	2.0
RbtR	pSymB	5.67	2.0	9.67	17.0
STM3633	pSymB	19.72	4.0	17.0	NA
SM-b20667	pSymB	3.18	1.0	4.0	0.0
PcaQ	pSymB	27.82	5.0	31.2	10.0
SM-b21706	pSymB	0.80	0.0	3.0	2.0
DctD	pSymB	1.24	1.0	0.0	0.0
ChpR	pSymB	1.88	0.0	0.4	0.0
ThuR	pSymB	37.63	7.0	36.0	28.0
SM-b21372	pSymB	7.33	2.0	3.5	0.0
SM-b21598	pSymB	3.51	1.0	3.4	1.0
YE2053	pSymB	19.47	4.0	13.0	6.0
RpoE9	pSymB	3.35	1.0	0.0	0.0
XylR	pSymB	22.61	5.0	24.2	2.0
SM-b20717	pSymB	15.24	4.0	19.25	11.0
SM-b20537	pSymB	7.77	3.0	12.0	1.0
ExpG	pSymB	6.0	2.0	2.0	NA

Regulatory network general statistics over the strains used in this study.

^a Position according to the Rm1021 reference strain;

^b Mean Absolute Deviation;

NA: not defined.