Possible expansion of cdb3 dimer at elevated pH.

To envision a possible high pH conformation of cdb3, the 2 peripheral protein binding domains were rotated away from their shared dimerization domain by allowing them to pivot at Gly 305 (indicated by arrows), a plausible site for rotation to occur. The resulting protein would be expected to remain dimeric, but also to become more elongated and fluorescent as the domains separate and the quenching H bonds between Asp 316 and Trp 105 (shown in red) disjoin.