Extended Data Fig. 6: Structural comparison of the C-terminal ___domain interface in S. elongatus and B. longum XPKs in the free form.
From: An ATP-sensitive phosphoketolase regulates carbon fixation in cyanobacteria
a. Left: structural superimposition of the dimer form between S. elongatus (dark/light blue) and B. longum (orange/gray) with RMSD 1.046 Å from 1291 Cα atoms of the respective dimer shows the C-terminal ___domain (in cartoon cylindrical presentation) interface of the subunits, mainly constituted of two helices from individual subunits. Middle: the approximate distance between the helices is 10 Å in S. elongatus, wider than 7.7 Å measured in B. longum XPK. Right: the view of the interface from above (circled with red dash lines). b. Stereo view showing the different residues and distances at the ATP-binding interface in the two XPKs. In addition to the narrower space between the helices compared to the S. elongatus, B. longum XPK has an Arg replacing H706 of SeXPK, Asn replacing R721, and Met replacing R753. Therefore, B. longum is unfavorable for ATP binding.
