Figure 6.

Single channel recording of the activity of the putative L-ArgR in planar lipid bilayers. Proteoliposomes containing protein from the first peak fractions off the Sephacryl S-300 elution were fused to planar lipid bilayers (DOPS:DOPE, 1:1) as described in Methods. (A). An initial control trace was obtained after addition proteoliposomes to the membrane bathing solution, before the addition of L-Arg. The three rows are from a continuous recording. (B). The addition of 10 μM L-Arg to the cis-side of the bilayer evoked regular periodic channel activity. A portion of this current record is shown at an expanded scale. (C). After several minutes of recording, the addition of 100 μM D-Arg to the cis-side resulted in the cessation of activity. Transmembrane potential was -100 mV. Traces shown in all panels are continuous records of that specific condition.