1A04

THE STRUCTURE OF THE NITRATE/NITRITE RESPONSE REGULATOR PROTEIN NARL IN THE MONOCLINIC C2 CRYSTAL FORM

1A04 の概要

• エントリーDOI: 10.2210/pdb1a04/pdb
• 分子名称: NITRATE/NITRITE RESPONSE REGULATOR PROTEIN NARL (2 entities in total)
• 機能のキーワード: signal transduction protein, response regulators, two-component systems
• 由来する生物種: Escherichia coli
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 47657.25

構造登録者

Baikalov, I.,Schroder, I.,Kaczor-Grzeskowiak, M.,Cascio, D.,Gunsalus, R.P.,Dickerson, R.E. (登録日: 1997-12-08, 公開日: 1998-03-18, 最終更新日: 2024-05-22)

主引用文献

Baikalov, I.,Schroder, I.,Kaczor-Grzeskowiak, M.,Cascio, D.,Gunsalus, R.P.,Dickerson, R.E.
NarL dimerization? Suggestive evidence from a new crystal form
Biochemistry, 37:3665-3676, 1998

PubMed Abstract: The structure of the Escherichia coli response regulator NarL has been solved in a new, monoclinic space group, and compared with the earlier orthorhombic crystal structure. Because the monoclinic crystal has two independent NarL molecules per asymmetric unit, we now have three completely independent snapshots of the NarL molecule: two from the monoclinic form and one from the orthorhombic. Comparison of these three structures shows the following: (a) The pairing of N and C domains of the NarL molecule proposed from the earlier analysis is in fact correct, although the polypeptide chain connecting domains was, and remains, disordered and not completely visible. The new structure exhibits identical relative orientation of N and C domains, and supplies some of the missing residues, leaving a gap of only seven amino acids. (b) Examination of corresponding features in the three independent NarL molecules shows that deformations in structure produced by crystal packing are negligible. (c) The "telephone receiver" model of NarL activation is confirmed. The N domain of NarL blocks the binding of DNA to the C domain that would be expected from the helix-turn-helix structure of the C domain. Hence, binding can only occur after significant displacement of N and C domains. (d) NarL monomers have a strong tendency toward dimerization involving contacts between helixes alpha 1 in the two monomers, and this may have mechanistic significance in DNA binding. Analogous involvement of helix alpha 1 in intermolecular contacts is also found in UhpA and in the CheY/CheZ complex.

PubMed: 9521685
DOI: 10.1021/bi972365a

実験手法

X-RAY DIFFRACTION (2.2 Å)