1.1.99.20	from a symbiotic mixed culture E-1, consisting of Sphingomonas terrae and a Rhizobium sp.	
1.1.99.20	mixed culture, using precipitation with ammonium sulfate, solubilization with laurylbetaine and chromatography with diethylamino-ethyl-cellulose, hydroxylapatite and Sephadex G-200	
1.1.99.20	Ni-NTA affinity chromatography	
1.1.99.20	strain No. 203, by precipitation with ammonium sulfate, solubilization with benzalkonium chloride, chromatography with DEAE-Toyopearl 650M and hydroxylapatite and gel filtration on Toyopearl HW-55