Abstract
The recombinant N-terminal fragment (amino acids 14-162) of a tetrameric voltage-gated potassium channel (K(V)1.1) has been studied using spectroscopic techniques. Evidence is presented that it forms a tetramer in aqueous solution, whereas when solubilised in 1% Triton X-100 it remains monomeric. The secondary structure content of both monomeric and tetrameric K,1.1 N-terminal fragment has been estimated from FTIR and CD spectroscopy to be 20-25% a-helix, 20-25% β-sheet, 20% turns and 30-40% random coil. Solubilisation of the protein in detergent is shown by hydrogen-deuterium exchange analysis to alter tertiary structure rather than secondary structure and this may be the determining factor in tetramerisation ability. Using molecular modelling we propose a super secondary structure consisting of two structural domains.
Original language | English |
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Pages (from-to) | 71-78 |
Journal | Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology |
Volume | 1341 |
DOIs | |
Publication status | Published - 1997 |