2MW2

Hha-H-NS46 charge zipper complex

Summary for 2MW2

• Entry DOI: 10.2210/pdb2mw2/pdb
• Related: 1jw2 1NI8
• NMR Information: BMRB: 25296
• Descriptor: Hemolysin expression-modulating protein Hha, DNA-binding protein H-NS (2 entities in total)
• Functional Keywords: nucleoid-associated proteins, charge-zipper complex, electrostatic-driven function, salt-dependent dynamics, dna binding protein
• Biological source: Escherichia coli K-12; More
• Cellular location: Cytoplasm, nucleoid : P0ACF8
• Total number of polymer chains: 3
• Total formula weight: 19576.48

Authors

Cordeiro, T.N.,Garcia, J.,Bernado, P.,Millet, O.,Pons, M. (deposition date: 2014-10-24, release date: 2015-07-29, Last modification date: 2024-05-01)

Primary citation

Cordeiro, T.N.,Garcia, J.,Bernado, P.,Millet, O.,Pons, M.
A Three-protein Charge Zipper Stabilizes a Complex Modulating Bacterial Gene Silencing.
J. Biol. Chem., 290:21200-21212, 2015

PubMed Abstract: The Hha/YmoA nucleoid-associated proteins help selectively silence horizontally acquired genetic material, including pathogenicity and antibiotic resistance genes and their maintenance in the absence of selective pressure. Members of the Hha family contribute to gene silencing by binding to the N-terminal dimerization domain of H-NS and modifying its selectivity. Hha-like proteins and the H-NS N-terminal domain are unusually rich in charged residues, and their interaction is mostly electrostatic-driven but, nonetheless, highly selective. The NMR-based structural model of the complex between Hha/YmoA and the H-NS N-terminal dimerization domain reveals that the origin of the selectivity is the formation of a three-protein charge zipper with interdigitated complementary charged residues from Hha and the two units of the H-NS dimer. The free form of YmoA shows collective microsecond-millisecond dynamics that can by measured by NMR relaxation dispersion experiments and shows a linear dependence with the salt concentration. The number of residues sensing the collective dynamics and the population of the minor form increased in the presence of H-NS. Additionally, a single residue mutation in YmoA (D43N) abolished H-NS binding and the dynamics of the apo-form, suggesting the dynamics and binding are functionally related.

PubMed: 26085102
DOI: 10.1074/jbc.M114.630400

Experimental method

SOLUTION NMR