Study of pore-forming capacity of detergent extracts of <i>C. jeikeium</i>.

<p>(A) Single-channel recording of a PC/<i>n</i>-decane membrane in the presence of the detergent extract of whole <i>C. jeikeium</i> K411 cells. The aqueous phase contained 1 M KCl, pH 6 and 50 ng/ml protein extract. The applied membrane potential was 20 mV; T = 20°C. (B) Histogram of the probability P(G) for the occurrence of a given conductivity unit observed with membranes formed of 1% PC dissolved in <i>n</i>-decane. It was calculated by dividing the number of fluctuations with a given conductance rise by the total number of conductance fluctuations in the presence of detergent extracts of whole <i>C. jeikeium</i> K411 cells. Two frequent conductive units were observed for 307 single events taken from 13 individual membranes. The average conductance of the steps corresponding to the left-side maximum was 1.25 nS and that of the right-side maximum was 2.5 nS. The aqueous phase contained 1 M KCl, pH 6 and 50 ng/ml protein extract, the applied membrane potential was 20 mV, T = 20°C.