PDBsum entry 1hh8

Cell cycle

PDB id: 1hh8

Contents

Protein chain

192 a.a. *

Ligands

FLC

Waters ×160

* Residue conservation analysis

PDB id:

1hh8

Name:

Cell cycle

Title:

The active n-terminal region of p67phox: structure at 1.8 angstrom resolution and biochemical characterizations of the a128v mutant implicated in chronic granulomatous disease

Structure:

Neutrophil cytosol factor 2. Chain: a. Fragment: n-terminal domain, residues 1-213. Synonym: p67phox, ncf-2. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Cell: neutrophil. Cellular_location: cytoplasm. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Resolution:

1.80Å R-factor: 0.182 R-free: 0.204

Authors:

S.Grizot,F.Fieschi,M.-C.Dagher,E.Pebay-Peyroula

Key ref:

S.Grizot et al. (2001). The active N-terminal region of p67phox. Structure at 1.8 A resolution and biochemical characterizations of the A128V mutant implicated in chronic granulomatous disease. J Biol Chem, 276, 21627-21631. PubMed id: 11262407 DOI: 10.1074/jbc.M100893200

Date:

21-Dec-00 Release date: 13-Jun-01

Protein chain

P19878  (NCF2_HUMAN) -  Neutrophil cytosol factor 2 from Homo sapiens

Seq: 526 a.a.

Struc: 192 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

DOI no: 10.1074/jbc.M100893200

J Biol Chem 276:21627-21631 (2001)

PubMed id: 11262407

The active N-terminal region of p67phox. Structure at 1.8 A resolution and biochemical characterizations of the A128V mutant implicated in chronic granulomatous disease.

S.Grizot, F.Fieschi, M.C.Dagher, E.Pebay-Peyroula.

ABSTRACT

Upon activation, the NADPH oxidase from neutrophils produces superoxide anions in response to microbial infection. This enzymatic complex is activated by association of its cytosolic factors p67(phox), p47(phox), and the small G protein Rac with a membrane-associated flavocytochrome b(558). Here we report the crystal structure of the active N-terminal fragment of p67(phox) at 1.8 A resolution, as well as functional studies of p67(phox) mutants. This N-terminal region (residues 1-213) consists mainly of four TPR (tetratricopeptide repeat) motifs in which the C terminus folds back into a hydrophobic groove formed by the TPR domain. The structure is very similar to that of the inactive truncated form of p67(phox) bound to the small G protein Rac previously reported, but differs by the presence of a short C-terminal helix (residues 187-193) that might be part of the activation domain. All p67(phox) mutants responsible for Chronic Granulomatous Disease (CGD), a severe defect of NADPH oxidase function, are localized in the N-terminal region. We investigated two CGD mutations, G78E and A128V. Surprisingly, the A128V CGD mutant is able to fully activate the NADPH oxidase in vitro at 25 degrees C. However, this point mutation represents a temperature-sensitive defect in p67(phox) that explains its phenotype at physiological temperature.

Selected figure(s)

Figure 1.
Fig. 1. Experimental electron density. The experimental map at 1.8 Å resolution (contoured at 1 ) is clearly interpretable and side chains are easily identified.

Figure 6.
Fig. 6. Environment of Ala-128. The figure shows the interactions of the extended C terminus (red) with TPR4 (green). Ala-128 is tightly packed in this environment. Valine at position 128 (light gray) is superimposed on alanine.

The above figures are reprinted by permission from the ASBMB: J Biol Chem (2001, 276, 21627-21631) copyright 2001.

Figures were selected by the author.