nod	nodulation
nif	nitrogen fixation
NFR	nodulation factor receptor
NCR	nodule-specific cysteine-rich
IRLC	inverted repeat lacking clade
SNF	symbiotic nitrogen fixation
HGT	horizontal gene transfer
NF	nodulation factor
T1SS	type I secretion system
T3SS	type III secretion system
T4SS	type IV secretion system
T6SS	type VI secretion system
NO	nitric oxide
IS	insertion sequence
TE	transposable element
EPS	exopolysaccharide
APS	arabinose-containing polysaccharide
IAA	indole-3-acetic acid
ChIP-seq	chromatin immunoprecipitation sequencing
Sf	Sinorhizobium fredii
Sm	Sinorhizobium meliloti
Rt	Rhizobium tropici
Ml	Mesorhizobium loti
Bd	Bradyrhizobium diazoefficiens