2MD0 | pdb_00002md0

Solution structure of ShK-like immunomodulatory peptide from Ancylostoma caninum (hookworm)

• PDB DOI: https://doi.org/10.2210/pdb2MD0/pdb
• BMRB: 19460

• Classification: IMMUNE SYSTEM
• Organism(s): Ancylostoma caninum
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2013-08-28 Released: 2014-07-02 
• Deposition Author(s): Chhabra, S., Swarbrick, J.D., Mohanty, B., Chang, S.C., Chandy, G.K., Pennington, M.W., Norton, R.S.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 30 
• Selection Criteria: structures with the lowest energy 

Literature

Kv1.3 channel-blocking immunomodulatory peptides from parasitic worms: implications for autoimmune diseases.

Chhabra, S., Chang, S.C., Nguyen, H.M., Huq, R., Tanner, M.R., Londono, L.M., Estrada, R., Dhawan, V., Chauhan, S., Upadhyay, S.K., Gindin, M., Hotez, P.J., Valenzuela, J.G., Mohanty, B., Swarbrick, J.D., Wulff, H., Iadonato, S.P., Gutman, G.A., Beeton, C., Pennington, M.W., Norton, R.S., Chandy, K.G.

(2014) FASEB J 28: 3952-3964

• PubMed: 24891519 
• DOI: https://doi.org/10.1096/fj.14-251967
• Primary Citation Related Structures: 
  2MCR, 2MD0


• PubMed Abstract: 
  

  The voltage-gated potassium (Kv) 1.3 channel is widely regarded as a therapeutic target for immunomodulation in autoimmune diseases. ShK-186, a selective inhibitor of Kv1.3 channels, ameliorates autoimmune diseases in rodent models, and human phase 1 trials of this agent in healthy volunteers have been completed. In this study, we identified and characterized a large family of Stichodactyla helianthus toxin (ShK)-related peptides in parasitic worms. Based on phylogenetic analysis, 2 worm peptides were selected for study: AcK1, a 51-residue peptide expressed in the anterior secretory glands of the dog-infecting hookworm Ancylostoma caninum and the human-infecting hookworm Ancylostoma ceylanicum, and BmK1, the C-terminal domain of a metalloprotease from the filarial worm Brugia malayi. These peptides in solution adopt helical structures closely resembling that of ShK. At doses in the nanomolar-micromolar range, they block native Kv1.3 in human T cells and cloned Kv1.3 stably expressed in L929 mouse fibroblasts. They preferentially suppress the proliferation of rat CCR7(-) effector memory T cells without affecting naive and central memory subsets and inhibit the delayed-type hypersensitivity (DTH) response caused by skin-homing effector memory T cells in rats. Further, they suppress IFNγ production by human T lymphocytes. ShK-related peptides in parasitic worms may contribute to the potential beneficial effects of probiotic parasitic worm therapy in human autoimmune diseases.

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Organizational Affiliation: 
• Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia;
Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California, USA; Department of Pharmacology, University of California, Davis, California, USA;
Department of Molecular Physiology and Biophysics, Graduate Program in Molecular Physiology and Biophysics, and.
Department of Molecular Physiology and Biophysics, Interdepartmental Graduate Program in Translational Biology and Molecular Medicine, and.
Kineta, Inc., Seattle, Washington, USA;
Peptides International, Louisville, Kentucky, USA;
Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California, USA;
Department of Microbiology, Immunology, and Tropical Medicine, The George Washington University, Washington D.C., USA; and Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.
Sabin Vaccine Institute and Texas Children's Hospital Center for Vaccine Development, National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas, USA;
Vector Molecular Biology Section, Laboratory of Malaria and Vector Research, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.
Department of Pharmacology, University of California, Davis, California, USA;
Department of Molecular Physiology and Biophysics.
Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia; [e-mail] [e-mail].
Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California, USA; [e-mail] [e-mail].

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 5.86 kDa 
• Atom Count: 403 
• Modeled Residue Count: 51 
• Deposited Residue Count: 51 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
AcK1	A	51	Ancylostoma caninum	Mutation(s): 0
UniProt
Find proteins for A0A016UNP9 (Ancylostoma ceylanicum) Explore A0A016UNP9  Go to UniProtKB:  A0A016UNP9

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 30 
• Selection Criteria: structures with the lowest energy 

Structure Validation

Entry History 

Deposition Data

• Released Date: 2014-07-02 
Deposition Author(s): Chhabra, S., Swarbrick, J.D., Mohanty, B., Chang, S.C., Chandy, G.K., Pennington, M.W., Norton, R.S.

Revision History  

• Version 1.0: 2014-07-02
  Type: Initial release
  
• Version 1.1: 2015-04-08
  Changes: Database references
• Version 1.2: 2023-06-14
  Changes: Data collection, Database references, Other
• Version 1.3: 2024-10-16
  Changes: Data collection, Database references, Structure summary