1DPE image
Deposition Date 1995-07-25
Release Date 1996-08-17
Last Version Date 2024-10-30
Entry Detail
PDB ID:
1DPE
Title:
DIPEPTIDE-BINDING PROTEIN
Biological Source:
Source Organism:
Method Details:
Experimental Method:
Resolution:
2.00 Å
R-Value Work:
0.16
Space Group:
P 21 21 21
Macromolecular Entities
Polymer Type:polypeptide(L)
Molecule:DIPEPTIDE-BINDING PROTEIN
Gene (Uniprot):dppA
Chain IDs:A
Chain Length:507
Number of Molecules:1
Biological Source:Escherichia coli K12
Ligand Molecules
Primary Citation
2 A resolution structure of DppA, a periplasmic dipeptide transport/chemosensory receptor.
Biochemistry 34 16585 16595 (1995)
PMID: 8527431 DOI: 10.1021/bi00051a006

Abstact

The family of about 50 periplasmic binding proteins, which exhibit diverse specificity (e.g., carbohydrates, amino acids, dipeptides, oligopeptides, oxyanions, metals, and vitamins) and range in size from 20 to 58 kDa, is a gold mine for an atomic-level investigation of structure and molecular recognition. These proteins serve as initial receptors for active transport systems or permeases. About six of these proteins, including the dipeptide-binding protein (DppA), are also primary receptors for chemotaxis. The structure of the unbound form of DppA (M(r) = 57,400) has been determined and refined to an R-factor of 0.169 to 2 A resolution. DppA consists of two distinct domains (I and II) connected by two "hinge" segments which form part of the base of the wide groove between the two domains. The relative orientation of the two domains gives the protein a pearlike shape, with domain I and domain II forming the larger and smaller apical ends, respectively. From the tip to the rounded bottom measures about 85 A, and the widest diameter is about 60 A. Domain I, which consists of two integrated subdomains, is folded from two separate polypeptide segments from the amino- and carboxyl-terminal ends. The more compact domain II is formed from the intervening segment. Comparison of the dipeptide-binding protein structure with that of the bound form of the similar oligopeptide-binding protein [Tame, J. R. H., Murshudov, G. N., Dodson, E. J., Neil, T. K., Dodson, G. G., Higgins, C. F., & Wilkinson, A. J. (1994) Science 264, 1578-1581] reveals the major features that differentiate the ligand specificity of the two proteins and describe the large hinge bending (about 55 degrees) between the two domains.

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Primary Citation of related structures