Inhibition of CMP-sialic acid transport by endogenous 5-methyl CMP
Fig 5
Comparison of the m5CMP and CMP binding sites.
A) A close-up of the substrate binding pocket is shown for both the CST-m5CMP (green) and CST-CMP (blue) structures. Only substrate-interacting side chains are shown and portions of TM8 are hidden for clarity. B and C) A slice through the surface representation of the substrate-binding cavity is shown for the CST-m5CMP (B) and CST-CMP (C) structures. The atoms for the pyrimidine ring are numbered. A black line is added as a visual aide to indicate where the cavity volume was sliced. The view is similar to that shown in panel A but is adjusted slightly to better show the part of the substrate-binding cavity that interacts with the C-5 methyl.