Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Biological Assembly 2  

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

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 67.66 kDa 
• Atom Count: 4,756 
• Modelled Residue Count: 574 
• Deposited Residue Count: 584 
• Unique protein chains: 1

 1JQD

Crystal Structure Analysis of Human Histamine Methyltransferase (Thr105 Polymorphic Variant) Complexed with AdoHcy and Histamine

• PDB DOI:  https://doi.org/10.2210/pdb1JQD/pdb

• Classification: TRANSFERASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2001-08-06 Released: 2002-08-06 
• Deposition Author(s): Horton, J.R., Sawada, K., Nishibori, M., Zhang, X., Cheng, X.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.28 Å
• R-Value Free: 0.257 
• R-Value Work: 0.205 
• R-Value Observed: 0.211 

Literature

Two polymorphic forms of human histamine methyltransferase: structural, thermal, and kinetic comparisons.

Horton, J.R., Sawada, K., Nishibori, M., Zhang, X., Cheng, X.

(2001) Structure 9: 837-849

• PubMed: 11566133 
• DOI: https://doi.org/10.1016/s0969-2126(01)00643-8
• Primary Citation of Related Structures:  
  1JQD, 1JQE


• PubMed Abstract: 
  

Histamine plays important biological roles in cell-to-cell communication; it is a mediator in allergic responses, a regulator of gastric acid secretion, a messenger in bronchial asthma, and a neurotransmitter in the central nervous system. Histamine acts by binding to histamine receptors, and its local action is terminated primarily by methylation. Human histamine N-methyltransferase (HNMT) has a common polymorphism at residue 105 that correlates with the high- (Thr) and low- (Ile) activity phenotypes.

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Related Citations: 

• Histamine N-methyltransferase pharmacogenetics: association of a common functional polymorphism with asthma
  Yan, L., Galinsky, R.E., Bernstein, J.A., Liggett, S.B., Weinshilboum, R.M.
  (2000) Pharmacogenetics 10: 261

• Methylation pharmacogenetics: catechol O-methyltransferase, thiopurine methyltransferase, and histamine N-methyltransferase
  Weinshilboum, R.M., Otterness, D.M., Szumlanski, C.L.
  (1999) Annu Rev Pharmacol Toxicol 39: 19

• Human histamine N-methyltransferase gene: structural characterization and chromosomal location
  Aksoy, S., Raftogianis, R., Weinshilboum, R.M.
  (1996) Biochem Biophys Res Commun 219: 548

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Organizational Affiliation: 

Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA 30322, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Histamine N-Methyltransferase	A, B	292	Homo sapiens	Mutation(s): 0  Gene Names: HNMT EC: 2.1.1.8
UniProt & NIH Common Fund Data Resources
Find proteins for P50135 (Homo sapiens) Explore P50135  Go to UniProtKB:  P50135
PHAROS:  P50135

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SAH	C [auth A], E [auth B]	S-ADENOSYL-L-HOMOCYSTEINE C14 H20 N6 O5 S ZJUKTBDSGOFHSH-WFMPWKQPSA-N
HSM	D [auth A], F [auth B]	HISTAMINE C5 H9 N3 NTYJJOPFIAHURM-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
SAH	Binding MOAD:  1JQD	Ki: 6900 (nM) from 1 assay(s)
	BindingDB:  1JQD	Ki: min: 1.05e+4, max: 1.81e+4 (nM) from 2 assay(s)
	PDBBind:  1JQD	Ki: 6900 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.28 Å
• R-Value Free: 0.257 
• R-Value Work: 0.205 
• R-Value Observed: 0.211 
• Space Group: P 6

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 131.75	α = 90
b = 131.75	β = 90
c = 64.03	γ = 120

Software Package:

Software Name	Purpose
CNS	refinement
MAR345	data collection
SCALEPACK	data scaling
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2002-08-06 
Deposition Author(s): Horton, J.R., Sawada, K., Nishibori, M., Zhang, X., Cheng, X.

Revision History  

• Version 1.0: 2002-08-06
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2017-10-04
  Changes: Refinement description