9F7I | pdb_00009f7i

Crystal structure of Borrelia burgdorferi B31 CspZ in complex with human FH SCR6-7

• PDB DOI: https://doi.org/10.2210/pdb9F7I/pdb

• Classification: IMMUNE SYSTEM
• Organism(s): Borreliella burgdorferi B31, Homo sapiens
• Expression System: Escherichia coli BL21(DE3), Komagataella pastoris
• Mutation(s): No 


• Deposited: 2024-05-03 Released: 2024-12-25 
• Deposition Author(s): Brangulis, K., Surth, V., Marcinkiewicz, A.L., Akopjana, I., Kazaks, A., Bogans, J., Huber, A., Lin, Y.-P., Kraiczy, P.
• Funding Organization(s): Other government

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.85 Å
• R-Value Free: 
  0.261 (Depositor), 0.265 (DCC) 
• R-Value Work: 
  0.201 (Depositor), 0.213 (DCC) 
• R-Value Observed: 
  0.204 (Depositor) 

Starting Model: experimental

Literature

CspZ variant-specific interaction with factor H incorporates a metal site to support Lyme borreliae complement evasion.

Brangulis, K., Surth, V., Marcinkiewicz, A.L., Akopjana, I., Kazaks, A., Bogans, J., Huber, A., Lin, Y.P., Kraiczy, P.

(2025) J Biol Chem 301: 108083-108083

• PubMed: 39675703 
• DOI: https://doi.org/10.1016/j.jbc.2024.108083
• Primary Citation Related Structures: 
  9F7I


• PubMed Abstract: 
  

  Polymorphic microbial immune evasion proteins dictate the pathogen species- or strain-specific virulence. Metals can impact how microbial proteins confer host-pathogen interactions, but whether this activity can be allelically variable is unclear. Here, we investigate the polymorphic CspZ protein of Lyme disease spirochete bacteria to assess the role of metals in protein-protein interaction. CspZ facilitates evasion of the complement system, the first line of immune defense through binding to the complement regulator factor H (FH). By obtaining a high-resolution cocrystal CspZ-FH structure, we identified a zinc coordinating the binding of FH SCR6-7 domains to a Glu65 on a loop from CspZ of Borrelia burgdorferi B31. However, zinc is dispensable for human FH binding for CspZ orthologs with a different loop orientation and/or lacking this glutamate. Phylogenetic analysis of all known human FH-binding CspZ variants further grouped the proteins into three unique lineages correlating with loop sequences. This suggests multiple FH-binding mechanisms evolved through Lyme disease spirochete-host interactions. Overall, this multidisciplinary work elucidates how the allelically specific immune evasion role of metals is impacted by microbial protein polymorphisms.

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Organizational Affiliation: 
• Latvian Biomedical Research and Study Centre, Riga, Latvia; Department of Human Physiology and Biochemistry, Riga Stradins University, Riga, Latvia. Electronic address: [e-mail].
Goethe University Frankfurt, University Hospital of Frankfurt, Institute of Medical Microbiology and Infection Control, Frankfurt, Germany.
Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, New York, USA; Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts, USA.
Latvian Biomedical Research and Study Centre, Riga, Latvia.
Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, New York, USA; Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts, USA; Department of Biomedical Sciences, SUNY Albany, Albany, New York, USA. Electronic address: [e-mail].
Goethe University Frankfurt, University Hospital of Frankfurt, Institute of Medical Microbiology and Infection Control, Frankfurt, Germany. Electronic address: [e-mail].

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: gel filtration

Macromolecule Content 

• Total Structure Weight: 39.69 kDa 
• Atom Count: 2,743 
• Modeled Residue Count: 331 
• Deposited Residue Count: 342 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Complement regulator-acquiring surface protein 2 (CRASP-2)	A	218	Borreliella burgdorferi B31	Mutation(s): 0  Gene Names: cspZ, BB_H06
UniProt
Find proteins for O50665 (Borreliella burgdorferi (strain ATCC 35210 / DSM 4680 / CIP 102532 / B31)) Explore O50665  Go to UniProtKB:  O50665

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Complement factor H	B	124	Homo sapiens	Mutation(s): 0  Gene Names: CFH, HF, HF1, HF2
UniProt & NIH Common Fund Data Resources
Find proteins for P08603 (Homo sapiens) Explore P08603  Go to UniProtKB:  P08603
PHAROS:  P08603 GTEx:  ENSG00000000971

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SO4	D [auth B], E [auth B]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L
ZN	C [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.85 Å
• R-Value Free:  0.261 (Depositor), 0.265 (DCC) 
• R-Value Work:  0.201 (Depositor), 0.213 (DCC) 
• R-Value Observed: 0.204 (Depositor) 

Space Group: P 2 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 44.661	α = 90
b = 67.095	β = 90
c = 143.602	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
XDS	data reduction
Aimless	data scaling
PHASER	phasing

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2024-12-25 
Deposition Author(s): Brangulis, K., Surth, V., Marcinkiewicz, A.L., Akopjana, I., Kazaks, A., Bogans, J., Huber, A., Lin, Y.-P., Kraiczy, P.

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Funding Organization	Location	Grant Number
Other government		lzp-2021/1-0068

Revision History  

• Version 1.0: 2024-12-25
  Type: Initial release
  
• Version 1.1: 2026-10-28
  Changes: Database references