To assess the suitability of transgenic peas as a host for protein production from the perspective of ease of recovery, a strain containing recombinant beta-glucuronidase with poly(histidine) tail (GUSH6) was evaluated for solubility of the target protein in relation to native components (proteins, carbohydrates, and phenolics). Recovery of the recombinant GUSH6 from aqueous extracts by immobilized metal affinity chromatography with coupled Co2+ yielded a nearly pure product with IDA (enrichment factor (EF) = 260) or NTA (EF = 200) resin. Single-step recoveries were also possible by isoelectric precipitation (EF = 4), polyelectrolyte precipitation (EF = 1.5), and anion-exchange chromatography (EF=3.1), but enrichment factors were low. (C) 2004 Wiley Periodicals, Inc.