Conserved serine in calnuc among various organisms
Conserved serine, histidine, and aspartic acid residues can be observed on the basis of the multiple sequence alignment (MSA) of calnuc from a variety of organisms. Residues forming the serine protease active site in calnuc among the different species are denoted. A, the Ser-224 residue although highly conserved among all of them except in Drosophila melanogaster may not be involved in the catalysis. B, Ser-378, Asp-238, and His-339 form the catalytic triad of the active site.