Design and characterization of a constitutively open KcsA.
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ABSTRACT:
SUBMITTER: Cuello LG
PROVIDER: S-EPMC2848999 | biostudies-literature | 2010 Mar
REPOSITORIES: biostudies-literature
Publications
Design and characterization of a constitutively open KcsA.
Cuello Luis G LG Jogini Vishwanath V Cortes D Marien DM Sompornpisut Amornrat A Purdy Michael D MD Wiener Michael C MC Perozo Eduardo E
FEBS letters 20100212 6
The molecular nature of the structure responsible for proton sensitivity in KcsA has been identified as a charge cluster that surrounds the inner helical bundle gate. Here, we show that this proton sensor can be modified to engineer a constitutively open form of KcsA, amenable to functional, spectroscopic and structural analyses. By combining charge neutralizations for all acidic and basic residues in the cluster at positions 25, 117-122 and 124 (but not E118), a mutant KcsA is generated that di ...[more]
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