PDBsum entry: 1azf

Hydrolase

PDB id: 1azf

Contents

Protein chain

129 a.a. *

Metals

_BR ×4

Waters ×85

* Residue conservation analysis

PDB id:

1azf

Name:

Hydrolase

Title:

Chicken egg white lysozyme crystal grown in bromide solution

Structure:

Lysozyme. Chain: a. Ec: 3.2.1.17

Source:

Gallus gallus. Chicken. Organism_taxid: 9031. Cell: egg. Cellular_location: cytoplasm (white)

Resolution:

1.80Å R-factor: 0.193 R-free: 0.240

Authors:

K.Lim,A.Nadarajah,E.L.Forsythe,M.L.Pusey

Key ref:

K.Lim et al. (1998). Locations of bromide ions in tetragonal lysozyme crystals. Acta Crystallogr D Biol Crystallogr, 54, 899-904. PubMed id: 9757106 DOI: 10.1107/S0907444998002844

Date:

17-Nov-97 Release date: 25-Feb-98

Protein chain

P00698  (LYSC_CHICK) -  Lysozyme C

Seq: 147 a.a.

Struc: 129 a.a.

Enzyme reactions

• Enzyme class: E.C.3.2.1.17 - Lysozyme.
• Reaction: Hydrolysis of the 1,4-beta-linkages between N-acetyl-D-glucosamine and N-acetylmuramic acid in peptidoglycan heteropolymers of the prokaryotes cell walls.

 Gene Ontology (GO) functional annotation 

• Cellular component: extracellular region (2 terms)
• Biological process: metabolic process (4 terms)
• Biochemical function: catalytic activity (5 terms)

DOI no: 10.1107/S0907444998002844

Acta Crystallogr D Biol Crystallogr 54:899-904 (1998)

PubMed id: 9757106

Locations of bromide ions in tetragonal lysozyme crystals.

K.Lim, A.Nadarajah, E.L.Forsythe, M.L.Pusey.

ABSTRACT

Anions have been shown to play a dominant role in the crystallization of chicken egg-white lysozyme from salt solutions. Previous studies employing X-ray crystallography have found one chloride ion binding site in the tetragonal crystal form of the protein and four nitrate ion binding sites in the monoclinic form. In this study the anion positions in the tetragonal form were determined from the difference Fourier map obtained from lysozyme crystals grown in bromide and chloride solutions. Five possible anion-binding sites were found in this manner. Some of these sites were in pockets containing basic residues while others were near neutral, but polar, residues. The sole chloride ion binding site found in previous studies was confirmed, while four further sites were found which corresponded to the four binding sites found for nitrate ions in monoclinic crystals. The study suggests that most of the anion-binding sites in lysozyme remain unchanged even when different anions and different crystal forms of lysozyme are employed.

Selected figure(s)

Figure 3.
Fig. 3. Stereo image of the Hal5 site. Given its relatively small peak in the electron-density difference map (~5a), the location of a bromide ion here is not certain and is assigned to a water molecule in the refined structure. However, other evidence suggests that this is indeed a valid anion-binding sitc for lysozyme (see text).

The above figure is reprinted by permission from the IUCr: Acta Crystallogr D Biol Crystallogr (1998, 54, 899-904) copyright 1998.

Figure was selected by an automated process.