1FD6:
reference: Designed protein G core variants fold to native-like structures: sequence selection by ORBIT tolerates variation in backbone specification., Ross SA, Sarisky CA, Su A, Mayo SL, Protein Sci 2001 Feb;10(2):450-4. PMID: 11266631

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).