A model for the interaction of a π protein monomer with R6K γ ori
iteron DNA. The crystal structure for a variant π monomer bound to an iteron was solved by
Swan et al. (2006) and deposited as a PDB file (PDB ID: 2NRA)
to the Worldwide Protein Data Bank (www.pdb.org). The model shown was
rendered using Protein Workshop 3.9 software (Moreland et al.,
2005) and colors were enhanced using Adobe Photoshop 11.0.2. DNA strands (ball and stick
representation) are light & dark gray with the TGAG(n)G motif in fuchsia. Amino acids predicted
and/or shown to contact bases of the DNA (Swan et al., 2006;
Kunnimalaiyaan et al., 2007, Saxena et al., 2010b) and shown in CPK are: Ser71, Tyr,74, Arg75, Asp129, Glu130, Gly131,
Arg225, Asp226, “Arg254”, and Ile256. The PDB file does not account for Arg254 in its
entirety. Atoms of CPK amino acids are colored as follows: C is white, N is blue, O is red. The
remainder of the π monomer is represented as a chain color ramp from blue (start) to red
(end) with helices and strands represented as cylinders and arrows, respectively.