1P71

Anabaena HU-DNA corcrystal structure (TR3)

Summary for 1P71

• Entry DOI: 10.2210/pdb1p71/pdb
• Related: 1B8Z 1IHF 1P51 1P78
• Descriptor: 5'-D(*TP*GP*CP*TP*TP*AP*TP*CP*AP*AP*TP*TP*TP*GP*TP*TP*GP*CP*AP*CP*C)-3', DNA-binding protein HU (3 entities in total)
• Functional Keywords: protein-dna complex, dna bending, hu, dna binding protein-dna complex, dna binding protein/dna
• Biological source: Anabaena sp.; More
• Total number of polymer chains: 4
• Total formula weight: 32937.43

Authors

Swinger, K.S.,Lemberg, K.M.,Zhang, Y.,Rice, P.A. (deposition date: 2003-04-30, release date: 2003-05-13, Last modification date: 2023-08-16)

Primary citation

Swinger, K.S.,Lemberg, K.M.,Zhang, Y.,Rice, P.A.
Flexible DNA bending in HU-DNA cocrystal structures
Embo J., 22:3749-3760, 2003

PubMed Abstract: HU and IHF are members of a family of prokaryotic proteins that interact with the DNA minor groove in a sequence-specific (IHF) or non-specific (HU) manner to induce and/or stabilize DNA bending. HU plays architectural roles in replication initiation, transcription regulation and site-specific recombination, and is associated with bacterial nucleoids. Cocrystal structures of Anabaena HU bound to DNA (1P71, 1P78, 1P51) reveal that while underlying proline intercalation and asymmetric charge neutralization mechanisms of DNA bending are similar for IHF and HU, HU stabilizes different DNA bend angles ( approximately 105-140 degrees ). The two bend angles within a single HU complex are not coplanar, and the resulting dihedral angle is consistent with negative supercoiling. Comparison of HU-DNA and IHF-DNA structures suggests that sharper bending is correlated with longer DNA binding sites and smaller dihedral angles. An HU-induced bend may be better modeled as a hinge, not a rigid bend. The ability to induce or stabilize varying bend angles is consistent with HU's role as an architectural cofactor in many different systems that may require differing geometries.

PubMed: 12853489
DOI: 10.1093/emboj/cdg351

Experimental method

X-RAY DIFFRACTION (1.9 Å)