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Fig. 1.
Model of the 5-LO N-terminal domain and
comparison with the cPLA2 C2 domain. A model of
the N-terminal domain of 5-LO was calculated (upper) based
upon the structure of rabbit reticulocyte 15-LO (6). The order
of the 
-strands is indicated by the gradual color shift from
blue to red, starting at the N terminus. Residues
regarded as potential Ca2+ ligands, which were subjected to
mutagenesis, are depicted in gray. The orientations of these
residues are based on the model without modeled Ca2+ ion(s)
and could be expected to change for the true ligands upon
Ca2+ binding. In the cPLA2 C2 domain
(lower; Protein Data Bank code 1RLW (25); structure
determined with Ca2+ present), the reported
Ca2+ ligands (25) are depicted in red.
