5VRF:
reference: Structural basis for the alternating access mechanism of the cation diffusion facilitator YiiP., Lopez-Redondo ML, Coudray N, Zhang Z, Alexopoulos J, Stokes DL, Proc Natl Acad Sci U S A. 2018 Mar 5. pii: 1715051115. doi:, 10.1073/pnas.1715051115. PMID: 29507252

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