Recombinant expression, purification and characterization of Kch, a putative Escherichia coli potassium channel protein.
The Escherichia coli gene kch, similar in primary structure to eukaryotic voltage-gated potassium channels, was cloned and overexpressed in E. coli. The protein was solubilized from the plasma membrane with dodecylmaltopyranoside, lauryldimethylamine oxide or N-laurylsarcosine and was purified in milligram amounts by imidazole elution from a nickel-chelate column. The molecular mass of the purified protein in a number of detergents with 12 carbon atom chains suggests that rKch forms primarily tetramers of the 50 kDa monomers. CD spectroscopy of the purified protein indicates a significant alpha-helical content that is preserved upon addition of SDS.
Voges
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Lawrence Berkeley National Laboratory, Division of Life Sciences, Berkeley, CA 94720, USA. voges@biochem.mpg.de
Jap
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BK
D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D004926:Escherichia coli / Q000737:chemistry* / Q000235:genetics; D029968:Escherichia coli Proteins; D008565:Membrane Proteins / Q000302:isolation & purification; D015221:Potassium Channels / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D015221:Potassium Channels; C101871:kch protein, E coli