Role of the irreplaceable residues in the LacY alternating access mechanism.

@article{Zhou2012RoleOT,
  title={Role of the irreplaceable residues in the LacY alternating access mechanism.},
  author={Yonggang Zhou and Xiaoxu Jiang and H Ronald Kaback},
  journal={Proceedings of the National Academy of Sciences of the United States of America},
  year={2012},
  volume={109 31},
  pages={
          12438-42
        }
}
Few side chains in the galactoside/H(+) symporter LacY (lactose permease of Escherichia coli) are irreplaceable for an alternating access mechanism in which sugar binding induces closing of the cytoplasmic cavity and reciprocal opening of a periplasmic cavity. In this study, each irreplaceable residue was mutated individually, and galactoside-induced opening or closing of periplasmic or cytoplasmic cavities was probed by site-directed alkylation. Mutation of Glu126 (helix IV) or Arg144 (helix V… CONTINUE READING
BETA