Possible salt bridges between transmembrane alpha-helices of the lactose carrier of Escherichia coli.
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چکیده
منابع مشابه
Possible salt bridges between transmembrane alpha-helices of the lactose carrier of Escherichia coli.
Although it is energetically extremely unfavorable to have charged amino acid residues of a polypeptide in the hydrophobic environment of the membrane phospholipid bilayer, a few such charged residues are found in membrane-spanning regions of membrane proteins. Ion pairs (salt bridges) would be much more stable in low dielectric media than single ionized residues. This paper provides indirect e...
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Intermolecular thiol cross-linking was used to determine surface-exposed positions in 250 lactose permease mutants containing single-Cys replacements in each transmembrane helix. Significant cross-linking of monomers to produce homodimers is observed in nine mutants with a 5-A-long cross-linking agent containing bis-methane thiosulfonate reactive groups [position 78 (helix III); positions 185, ...
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15 صفحه اولTOPTMH: Topology Predictor for Transmembrane alpha-Helices
Alpha-helical transmembrane proteins mediate many key biological processes and represent 20%-30% of all genes in many organisms. Due to the difficulties in experimentally determining their high-resolution 3D structure, computational methods to predict the location and orientation of transmembrane helix segments using sequence information are essential. We present TOPTMH, a new transmembrane hel...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1992
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(19)36751-1