Table 1. Classification and general features of E. meliloti AK58 and BO21CC according to the MIGS recommendations [9] and the Names for Life database [10].

MIGS ID	Property	Term	Evidence code
	Current classification	Domain Bacteria	TAS [11]
		Phylum Proteobacteria	TAS [12]
		Class Alphaproteobacteria	TAS [12]
		Order Rhizobiales	TAS [12]
		Family Rhizobiaceae	TAS [12]
		Genus Ensifer	TAS [2,12]
		Species Ensifer meliloti	TAS [13]
		Strain BO21CC      Strain AK58	TAS [4,5]
	Gram stain	negative	TAS [12]
	Cell shape	rods	TAS [12]
	Motility	Motile	TAS [12]
	Sporulation	non-sporulating	TAS [12]
	Temperature range	mesophile, 20-37°C	TAS [12]
	Optimum temperature	25-30°C	TAS [12]
	Salinity	Tolerate 1.0% NaCl	TAS [12]
MIGS-22	Oxygen requirement	Aerobe	TAS [12]
	Carbon source	carbohydrates and salts of organic acids	TAS [12]
	Energy metabolism	chemoorganotroph	TAS [12]
MIGS-6	Habitat	Soil, root nodules of legumes	TAS [3,12]
MIGS-15	Biotic relationship	free living, symbiont	TAS [12]
MIGS-14	Pathogenicity	not reported
	Biosafety level	1	TAS [14]
MIGS-23.1	Isolation	BO21CC: root nodules of Medicago sativa cv. ‘Oneida’      AK58: root nodules of Medicago falcata	TAS [4]
MIGS-4	Geographic location	BO21CC: Lodi, Italy      AK58: Kazakhstan,	TAS [4]
MIGS-5	Sample collection time	BO21CC: 1997      AK58: 2001	NAS
MIGS-4.1	Latitude	BO21CC: 45.31      AK58: 58.75	NAS
MIGS-4.2	Longitude	BO21CC: 9.50      AK58: 48.98	NAS
MIGS-4.3	Depth	not reported
MIGS-4.4	Altitude	BO21CC: 70 m      AK58: 305 m	NAS

Evidence codes - TAS: Traceable Author Statement (i.e., a direct report exists in the literature); NAS: Non-traceable Author Statement (i.e., not directly observed for the living, isolated sample, but based on a generally accepted property for the species, or anecdotal evidence). These evidence codes are from the Gene Ontology project [15].