Purification and characterization of agrocin 84.

A procedure for the rapid purification of milligram quantities of agrocin 84, a bacteriocin-like compound produced by Agrobacterium radiobacter strain K-84, has been developed. This procedure, which employs charcoal adsorption, ion-exchange, sieving chromatography, and continuous-flow electrophoresis, can yield agrocin 84 which is 65% pure on a dry weight basis. The purest preparations were strongly ultraviolet absorbing, with a maximum at 264 nm (epsilon 7.0/264 = 22,675 cm2 - M-1) and a minimum at 227 nm (ratio of 264 to 227 nm, 6.00). As has been reported, agrocin 84 contains an unusual phosphoramidate or 6-N-acyl linkage to adenine. Adenine, glucose, and phosphate are present in a 1:1:2 molar ratio. The molecular weight was estimated to be 1,350.