Abstract
Lactose permease of Escherichia coli (LacY) is highly dynamic, and sugar binding causes closing of a large inward-facing cavity with opening of a wide outward-facing hydrophilic cavity. Therefore, lactose/H(+) symport via LacY very likely involves a global conformational change that allows alternating access of single sugar- and H(+)-binding sites to either side of the membrane. Here, in honor of Stephan H. White's seventieth birthday, we review in camera the various biochemical/biophysical approaches that provide experimental evidence for the alternating access mechanism.
Publication types
-
Research Support, N.I.H., Extramural
-
Research Support, U.S. Gov't, Non-P.H.S.
-
Review
MeSH terms
-
Alkylation
-
Biological Transport / physiology*
-
Cysteine / chemistry
-
Escherichia coli Proteins / chemistry
-
Escherichia coli Proteins / metabolism*
-
Models, Molecular
-
Monosaccharide Transport Proteins / chemistry
-
Monosaccharide Transport Proteins / metabolism*
-
Protein Conformation
-
Symporters / chemistry
-
Symporters / metabolism*
-
Tryptophan / chemistry
Substances
-
Escherichia coli Proteins
-
LacY protein, E coli
-
Monosaccharide Transport Proteins
-
Symporters
-
Tryptophan
-
Cysteine