Biological Assembly 1  

Global Symmetry: Cyclic - C3  (3D View)
Global Stoichiometry: Hetero 6-mer - A3B3 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 210.42 kDa 
• Atom Count: 14,285 
• Modelled Residue Count: 1,767 
• Deposited Residue Count: 1,821 
• Unique protein chains: 2

 1FLC

X-RAY STRUCTURE OF THE HAEMAGGLUTININ-ESTERASE-FUSION GLYCOPROTEIN OF INFLUENZA C VIRUS

• PDB DOI: 10.2210/pdb1FLC/pdb

• Classification: HYDROLASE
• Organism(s): Influenza C virus (C/Johannesburg/1/66)
• Mutation(s): No 


• Deposited: 1999-02-22 Released: 2000-03-01 
• Deposition Author(s): Rosenthal, P.B., Zhang, X., Formanowski, F., Fitz, W., Wong, C.H., Meier-Ewert, H., Skehel, J.J., Wiley, D.C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.20 Å
• R-Value Free: 0.267 
• R-Value Work: 0.223 
• R-Value Observed: 0.223 

Literature

Structure of the haemagglutinin-esterase-fusion glycoprotein of influenza C virus.

Rosenthal, P.B., Zhang, X.

(1998) Nature 396: 92-96

• PubMed: 9817207 
• DOI: 10.1038/23974
• Primary Citation of Related Structures:  
  1FLC


• PubMed Abstract: 
  

The spike glycoproteins of the lipid-enveloped orthomyxoviruses and paramyxoviruses have three functions: to recognize the receptor on the cell surface, to mediate viral fusion with the cell membrane, and to destroy the receptor. In influenza C virus, a single glycoprotein, the haemagglutinin-esterase-fusion (HEF) protein, possesses all three functions. In influenza A and B, the first two activities are mediated by haemagglutinin and the third by a second glycoprotein, neuraminidase. Here we report the crystal structure of the HEF envelope glycoprotein of influenza C virus. We have identified the receptor-binding site and the receptor-destroying enzyme (9-O-acetylesterase) sites, by using receptor analogues. The receptor-binding domain is structurally similar to the sialic acid-binding domain of influenza A haemagglutinin, but binds 9-O-acetylsialic acid. The esterase domain has a structure similar to the esterase from Streptomyces scabies and a brain acetylhydrolase. The receptor domain is inserted into a surface loop of the esterase domain and the esterase domain is inserted into a surface loop of the stem. The stem domain is similar to that of influenza A haemagglutinin, except that the triple-stranded, alpha-helical bundle diverges at both of its ends, and the amino terminus of HEF2, the fusion peptide, is partially exposed. The segregation of HEF's three functions into structurally distinct domains suggests that the entire stem region, including sequences at the amino and carboxy termini of HEF1 which precede the post-translational cleavage site between HEF1 and HEF2, forms an independent fusion domain which is probably derived from an ancestral membrane fusion protein.

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Organizational Affiliation: 

Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
HAEMAGGLUTININ-ESTERASE-FUSION GLYCOPROTEIN	A, C, E	432	Influenza C virus (C/Johannesburg/1/66)	Mutation(s): 0  Gene Names: HE EC: 3.1.1.53
UniProt
Find proteins for P07975 (Influenza C virus (strain C/Johannesburg/1/1966)) Explore P07975  Go to UniProtKB:  P07975

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
HAEMAGGLUTININ-ESTERASE-FUSION GLYCOPROTEIN	B, D, F	175	Influenza C virus (C/Johannesburg/1/66)	Mutation(s): 0  Gene Names: HE EC: 3.1.1.53
UniProt
Find proteins for P07975 (Influenza C virus (strain C/Johannesburg/1/1966)) Explore P07975  Go to UniProtKB:  P07975

Oligosaccharides

Help

Entity ID: 3
Molecule	Chains	Chain Length	2D Diagram	Glycosylation
beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose	G, H, I, J, L, M, O, Q, R, S, T	3		N-Glycosylation
Glycosylation Resources
GlyTouCan:  G15407YE GlyCosmos:  G15407YE GlyGen:  G15407YE

Entity ID: 4
Molecule	Chains	Chain Length	2D Diagram	Glycosylation
alpha-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-alpha-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose	K, P, U	3		N-Glycosylation
Glycosylation Resources
GlyTouCan:  G52260VY GlyCosmos:  G52260VY GlyGen:  G52260VY

Entity ID: 5
Molecule	Chains	Chain Length	2D Diagram	Glycosylation
beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-alpha-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose	N	3		N-Glycosylation
Glycosylation Resources
GlyTouCan:  G35926TG GlyCosmos:  G35926TG GlyGen:  G35926TG

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.20 Å
• R-Value Free: 0.267 
• R-Value Work: 0.223 
• R-Value Observed: 0.223 
• Space Group: P 4₃ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 155.4	α = 90
b = 155.4	β = 90
c = 414.4	γ = 90

Software Package:

Software Name	Purpose
SCALEPACK	data scaling
X-PLOR	refinement

Structure Validation

Entry History 

Deposition Data

• Released Date: 2000-03-01 
Deposition Author(s): Rosenthal, P.B., Zhang, X., Formanowski, F., Fitz, W., Wong, C.H., Meier-Ewert, H., Skehel, J.J., Wiley, D.C.

Revision History  

• Version 1.0: 2000-03-01
  Type: Initial release
  
• Version 1.1: 2008-04-26
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Non-polymer description, Version format compliance
• Version 1.3: 2017-10-04
  Changes: Refinement description
• Version 2.0: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Advisory, Atomic model, Data collection, Derived calculations, Structure summary