Fig 5

Fig 5 Predicted structures of zebrafish s100 homodimers and heterodimers.

(A) A close-up of calprotectin’s (gray) hexa-histidine site coordinating a zinc ion (purple sphere) via polar contacts (dashed yellow lines). (B) A view of the calprotectin heterodimer from crystal structure PDB: 8JSC. Calcium ions are represented as green spheres. (C and D) are overlay views of AlphaFold3 model structure predictions of homodimers and heterodimers, respectively, aligned to the calprotectin heterodimer. The first chain of each model dimer is in blue, and the second chain is in green. This excludes the s100t homodimer (S7 Fig). (E and F) Histograms showing the number of predicted homodimer (E) and heterodimer (F) models that have a certain number of histidine alpha carbons within 9 Å of the calprotectin Zn²⁺ ion. Arrows indicate that human calprotectin has seven histidines within 9 Å of the Zn²⁺ ion.