FIGURE 2. A Rhizobiaceae membrane-lipid component is required for RgtA activity in E. coli.
Membranes of E. coli harboring pRgtA or the vector control pET23a were assayed under standard conditions at 0.25 mg/ml with or without the addition of 0.25 mg of total lipids extracted from S. meliloti 1021 or R. leguminosarum 3841, as indicated. GalA addition was judged by the shift of the Kdo2-1-dephospho-[4′-32P]lipid IVA band. Membranes of S. meliloti 1021/pRK-RgtA without added lipids were used as the positive control (lane 8).