Crystal structure of Helicobacter cinaedi CAIP

Experimental Data Snapshot

  • Resolution: 2.55 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.187 
  • R-Value Observed: 0.190 

wwPDB Validation   3D Report Full Report

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The Helicobacter cinaedi antigen CAIP participates in atherosclerotic inflammation by promoting the differentiation of macrophages in foam cells.

D'Elios, M.M.Vallese, F.Capitani, N.Benagiano, M.Bernardini, M.L.Rossi, M.Rossi, G.P.Ferrari, M.Baldari, C.T.Zanotti, G.de Bernard, M.Codolo, G.

(2017) Sci Rep 7: 40515-40515

  • DOI: https://doi.org/10.1038/srep40515

  • PubMed Abstract: 

    Recent studies have shown that certain specific microbial infections participate in atherosclerosis by inducing inflammation and immune reactions, but how the pathogens implicated in this pathology trigger the host responses remains unknown. In this study we show that Helicobacter cinaedi (Hc) is a human pathogen linked to atherosclerosis development since at least 27% of sera from atherosclerotic patients specifically recognize a protein of the Hc proteome, that we named Cinaedi Atherosclerosis Inflammatory Protein (CAIP) (n = 71). CAIP appears to be implicated in this pathology because atheromatous plaques isolated from atherosclerotic patients are enriched in CAIP-specific T cells (10%) which, in turn, we show to drive a Th1 inflammation, an immunopathological response typically associated to atherosclerosis. Recombinant CAIP promotes the differentiation and maintenance of the pro-inflammatory profile of human macrophages and triggers the formation of foam cells, which are a hallmark of atherosclerosis. This study identifies CAIP as a relevant factor in atherosclerosis inflammation linked to Hc infection and suggests that preventing and eradicating Hc infection could reduce the incidence of atherosclerosis.

  • Organizational Affiliation

    Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
A, B, C, D, E
A, B, C, D, E, F, G, H, I, J, K, L
145Helicobacter cinaediMutation(s): 0 
Gene Names: HCN_0606
Find proteins for I7H4K9 (Helicobacter cinaedi CCUG 18818 = ATCC BAA-847)
Explore I7H4K9 
Go to UniProtKB:  I7H4K9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupI7H4K9
Sequence Annotations
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
Query on FE

Download Ideal Coordinates CCD File 
M [auth A]
N [auth B]
O [auth C]
P [auth D]
Q [auth E]
M [auth A],
N [auth B],
O [auth C],
P [auth D],
Q [auth E],
R [auth F],
S [auth G],
T [auth H],
U [auth I],
V [auth J],
W [auth K],
X [auth L]
Experimental Data & Validation

Experimental Data

  • Resolution: 2.55 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.187 
  • R-Value Observed: 0.190 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 89.746α = 90
b = 135.918β = 114.5
c = 93.445γ = 90
Software Package:
Software NamePurpose
XDSdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report

Entry History & Funding Information

Deposition Data

Funding OrganizationLocationGrant Number

Revision History  (Full details and data files)

  • Version 1.0: 2017-04-26
    Type: Initial release
  • Version 1.1: 2024-01-10
    Changes: Data collection, Database references, Derived calculations, Refinement description