The influence of a membrane environment on the structure and stability of a prokaryotic potassium channel, KcsA.
The lack of a membrane environment in membrane protein crystals is considered one of the major limiting factors to fully imply X-ray structural data to explain functional properties of ion channels [Gulbis, J.M. and Doyle, D. (2004) Curr. Opin. Struct. Biol. 14, 440-446]. Here, we provide infrared spectroscopic evidence that the structure and stability of the potassium channel KcsA and its chymotryptic derivative 1-125 KcsA reconstituted into native-like membranes differ from those exhibited by these proteins in detergent solution, the latter taken as an approximation of the mixed detergent-protein crystal conditions.
Encinar
J A
JA
Instituto de Biología Molecular y Celular, Universidad Miguel Hernández, Elche, 03202 Alicante, Spain.
Molina
M L
ML
Poveda
J A
JA
Barrera
F N
FN
Renart
M L
ML
Fernández
A M
AM
González-Ros
J M
JM
D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism; D003902:Detergents / Q000737:chemistry; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005960:Glucosides / Q000737:chemistry; D008958:Models, Molecular; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015221:Potassium Channels / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D020836:Protein Structure, Quaternary; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared; D048170:Streptomyces lividans / Q000737:chemistry*
D001426:Bacterial Proteins; D003902:Detergents; D005960:Glucosides; D010446:Peptide Fragments; D015221:Potassium Channels; D011994:Recombinant Proteins; C107790:prokaryotic potassium channel; C040358:dodecyl maltoside