2ewt
From Proteopedia
Crystal structure of the DNA-binding domain of BldD
Overview
BldD is a central regulator of the developmental process in Streptomyces coelicolor. The 1.8 angstroms resolution structure of the DNA-binding domain of BldD (BldDN) reveals that BldDN forms a compact globular domain composed of four helices (alpha1-alpha4) containing a helix-turn-helix motif (alpha2-alpha3) resembling that of the DNA-binding domain of lambda repressor. The BldDN/DNA complex model led us to design a series of mutants, which revealed the important role of alpha3 and the 'turn' region between alpha2 and alpha3 for DNA recognition. Based on the fact that BldD occupies two operator sites of bldN and whiG and shows significant disparity in the affinity toward the two operator sites when they are disconnected, we propose a model of cooperative binding, which means that the binding of one BldD dimer to the high affinity site facilitates that of the second BldD dimer to the low affinity site. In addition, structural and mutational investigation reveals that the Tyr62Cys mutation, found in the first-identified bldD mutant, can destabilize BldD structure by disrupting the hydrophobic core.
About this Structure
2EWT is a Single protein structure of sequence from Streptomyces coelicolor. Full crystallographic information is available from OCA.
Reference
Crystal structure of the DNA-binding domain of BldD, a central regulator of aerial mycelium formation in Streptomyces coelicolor A3(2)., Kim IK, Lee CJ, Kim MK, Kim JM, Kim JH, Yim HS, Cha SS, Kang SO, Mol Microbiol. 2006 Jun;60(5):1179-93. PMID:16689794 Page seeded by OCA on Sun May 4 03:12:17 2008
