4KY9:
reference: A substrate access tunnel in the cytosolic domain is not an essential feature of the solute carrier 4 (SLC4) family of bicarbonate transporters., Shnitsar V, Li J, Li X, Calmettes C, Basu A, Casey JR, Moraes TF, Reithmeier RA, J Biol Chem. 2013 Nov 22;288(47):33848-60. doi: 10.1074/jbc.M113.511865. Epub, 2013 Oct 11. PMID: 24121512

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