Fig. 3: Crystal structures of TbGMPR C318A with or without GMP.

Cartoon representation of the octameric structures of C318A apo (relaxed form, a) and C318A/GMP (twisted form, b), each of which are composed of two tetramers. Tetramer 1 (subunits A–D) and tetramer 2 (subunits A′–D′) are colored in light and dark blue, respectively. GMP molecules are shown as yellow stick representations. Note that C318A/GMP (b; right panel) is compressed compared to C318A apo (a; right panel).