Fig. 3: Structure of the SpoIVFB Intramembrane Protease.
From: Substrate engagement by the intramembrane metalloprotease SpoIVFB
A Comparison of the SpoIVFB structure with the previous crystal structure of mjS2P in an open conformation (PDB: 3B4R). SpoIVFB is colored with the TM helices in transparent light blue, the interdomain linker in dark blue, and the CBS domain in green. mjS2P is colored in orange. The gray box delineates the approximate boundary of the lipid membrane. B Close-up view of the SpoIVFB and mjS2P zinc-binding site. SpoIVFB is colored blue, mjS2P is colored orange, and the zinc identified in the mjS2P structure is colored magenta. The cryo-EM map of WT SpoIVFB:Pro-σK is shown as a transparent gray surface. The cryo-EM map demonstrates that no zinc ion was co-purified with WT SpoIVFB:Pro-σK. Potential zinc-coordinating residue numbers are from SpoIVFB.
