Research at the SMRL
Wang, Y., Zhao, S., Somerville, R.L. and Jardetzky, O. "Solution Structure of
the DNA-binding Domain of the TyrR protein from Haemophilus Influenzae"
(2001) Protein Science 10, 592-598.
Wang, Y. and Jardetzky, O. "Structural study of TyrR protein of H. Influenzae"
Molecular Pharmacology Department Retreat, Sept 20-22, 2000, Asilomar.
Solution Structure of the DNA-binding Domain of the TyrR protein of
Wang, Y., Zhao, S., Somerville, R.L. and Jardetzky, O. (2001) Protein
Science 10, 592-598.
The TyrR protein of Haemophilus influenzae is a 36-kD transcription factor whose major function is to
control the expression of genes important in the biosynthesis and transport of aromatic amino acids. Using
1H and 15N NMR spectroscopy, we have determined the 3D solution structure of the TyrR C-terminal
DNA-binding domain (DBD) containing residues from 258 to 318 (TyrR[258-318]). The NMR results show
that this segment of TyrR consists of a potential hinge helix at its N terminus (residues 263-270) as well
as three well-defined alpha-helices extending from residues 277-289 (HR-2), 293-300 (HR-1), and 304-314
(HR). Helix HR-1 and HR fold in a typical helix-turn-helix (HTH) motif. The three helices and the hinge
helix are tightly bound together by hydrophobic interaction and hydrogen bonds. Several hydrophilic
residues whose side chains may directly interact with DNA are identified. A hydrophobic patch that may be
part of the interaction surface between the domains of TyrR protein is also observed. Comparisons with the
structures of other HTH DNA-binding proteins reveal that in terms of the spatial orientation of the three
helices, this protein most closely resembles the cap family.
Figure Caption. Ribbon diagram of the DNA-binding domain of the TyR protein as determined
Figure Caption. 15N-1H HSQC spectrum of the 256 residue, ligand-binding
domain of the TyrR protein from Haemophilus Influenzae.