1 research outputs found
Construction of a Ca<sup>2+</sup>-Gated Artificial Channel by Fusing Alamethicin with a Calmodulin-Derived Extramembrane Segment
Using native chemical ligation, we constructed a Ca<sup>2+</sup>-gated fusion channel protein consisting of alamethicin and
the C-terminal
domain of calmodulin. At pH 5.4 and in the absence of Ca<sup>2+</sup>, this fusion protein yielded a burst-like channel current with no
discrete channel conductance levels. However, Ca<sup>2+</sup> significantly
lengthened the specific channel open state and increased the mean
channel current, while Mg<sup>2+</sup> produced no significant changes
in the channel current. On the basis of 8-anilinonaphthalene-1-sulfonic
acid (ANS) fluorescent measurement, Ca<sup>2+</sup>-stimulated gating
may be related to an increased surface hydrophobicity of the extramembrane
segment of the fusion protein