==== Secondary Structure Definition by the program DSSP, updated CMBI version by ElmK / April 1,2000 ==== DATE=14-APR-2010 . REFERENCE W. KABSCH AND C.SANDER, BIOPOLYMERS 22 (1983) 2577-2637 . HEADER IMMUNE SYSTEM 21-DEC-06 2OCW . COMPND 2 MOLECULE: POLYMERIC-IMMUNOGLOBULIN RECEPTOR; . SOURCE 2 ORGANISM_SCIENTIFIC: HOMO SAPIENS; . AUTHOR A.BONNER,C.PERRIER,B.CORTHESY,S.J.PERKINS .