| 4ZB1: reference: Chromophore Deprotonation State Alters the Optical Properties of Blue Chromoprotein., Chiang CY, Lee CC, Lo SY, Wang AH, Tsai HJ, PLoS One. 2015 Jul 28;10(7):e0134108. doi: 10.1371/journal.pone.0134108., eCollection 2015. PMID: 26218063 |
This OCA 
Structure page
uses Jmol,
developed by the Jmol Development Team
(documentation).