PDBsum entry 2gk2

Cell adhesion

PDB id: 2gk2

Contents

Protein chain

109 a.a. *

Ligands

GOL ×3

Metals

_NI ×2

Waters ×75

* Residue conservation analysis

PDB id:

2gk2

Name:

Cell adhesion

Title:

Crystal structure of the n terminal domain of human ceacam1

Structure:

Carcinoembryonic antigen-related cell adhesion molecule 1. Chain: a, b. Fragment: n terminal domain (residues 63-170). Synonym: biliary glycoprotein 1, bgp-1, cd66 antigen, cd66a antigen. Engineered: yes

Source:

Homo sapiens. Human. Organism_taxid: 9606. Gene: ceacam1. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.20Å R-factor: 0.213 R-free: 0.258

Authors:

A.Fedarovich,J.Tomberg,R.A.Nicholas,C.Davies

Key ref:

A.Fedarovich et al. (2006). Structure of the N-terminal domain of human CEACAM1: binding target of the opacity proteins during invasion of Neisseria meningitidis and N. gonorrhoeae. Acta Crystallogr D Biol Crystallogr, 62, 971-979. PubMed id: 16929097 DOI: 10.1107/S0907444906020737

Date:

31-Mar-06 Release date: 05-Sep-06

Protein chains

P13688  (CEAM1_HUMAN) -  Carcinoembryonic antigen-related cell adhesion molecule 1 from Homo sapiens

Seq: 526 a.a.

Struc: 109 a.a.*

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

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1107/S0907444906020737

Acta Crystallogr D Biol Crystallogr 62:971-979 (2006)

PubMed id: 16929097

Structure of the N-terminal domain of human CEACAM1: binding target of the opacity proteins during invasion of Neisseria meningitidis and N. gonorrhoeae.

A.Fedarovich, J.Tomberg, R.A.Nicholas, C.Davies.

ABSTRACT

CEACAM1 is a cellular adhesion molecule whose protein expression is down-regulated in several carcinomas and which also contributes to the pathogenicity of Neisseria by acting as a receptor for Opa proteins. The crystal structure of the N-terminal (D1) domain of human CEACAM1 has been determined at 2.2 Angstrom resolution. The structure shows several differences compared with a lower resolution model of the same domain from mouse solved previously, especially in the functional regions. Mapping of the sites of mutations that lower or abolish the binding of CEACAM1 to Opa proteins shows a distinct clustering of residues on the GFCC'C'' face of the molecule. Prominent amongst these are residues in the C, C' and F strands and the CC' loop. A similar analysis shows that the region responsible for homophilic or heterophilic interactions of CEACAM1 is also on the GFCC'C'' face and overlaps partially with the Opa-binding region. This higher resolution structure of CEACAM1 will facilitate a more precise dissection of its functional regions in the context of neisserial pathogenesis, cellular adhesion and immune evasion.

Selected figure(s)

Figure 2.
Figure 2 A comparison of the D1 domains of human CEACAM1 and mouse CEACAM1a. The two structures were superimposed and are shown in backbone form with hCEACAM1 in black and mCEACAM1a in gray. Regions of the two structures that differ between the two molecules are noted with arrows and are labeled.

Figure 3.
Figure 3 Regions that differ significantly in structure between the D1 domains of human CEACAM1 and mouse CEACAM1a. In each stereoview, human CEACAM1 is colored orange and mouse CEACAM1a is colored green, with corresponding labels, except for those residues that are the same in each, which are colored black. Hydrogen-bonding interactions in human CEACAM are shown as dashed lines. (a) The CC' loop (b), the C''D loop and (c) the FG loop.

The above figures are reprinted by permission from the IUCr: Acta Crystallogr D Biol Crystallogr (2006, 62, 971-979) copyright 2006.

Figures were selected by an automated process.