The Cupin Protein Pac13 is Suggested by the Data to Be a Homodimer

Cupin proteins share a double‐stranded β‐helix fold, form one of the largest protein superfamilies, and possess remarkable functional diversity. They usually exist in homooligomeric states. Goss and co‐workers recently reported that the cupin protein Pac13, which is a dehydratase that mediates the formation of the 3′‐deoxy nucleoside of pacidamycins, is an unusual small monomer. However, a careful analysis of the biophysical and structural data provided by the authors suggests that Pac13 is in fact a homodimer, similar to many other cupin proteins.