Structural characterization and pH-induced conformational transition of full-length KcsA.

ABSTRACT: The bacterial K+ channel KcsA from Streptomyces lividans was analyzed by neutron and x-ray small-angle solution scattering. The C-terminally truncated version of KcsA, amenable to crystallographic studies, was compared with the full-length channel. Analyzing the scattering data in terms of radius of gyration reveals differences between both KcsA species of up to 13.2 A. Equally, the real-space distance distribution identifies a 40 to 50 A extension of full-length KcsA compared to its C-terminally truncated counterpart. We show that the x-ray and neutron scattering data are amenable for molecular shape reconstruction of full-length KcsA. The molecular envelopes calculated display an hourglass-shaped structure within the C-terminal intracellular domain. The C-terminus extends the membrane sp

SUBMITTER: Zimmer J 

PROVIDER: S-EPMC1367324 | biostudies-literature | 2006 Mar

REPOSITORIES: biostudies-literature