AC   MF_04207;
DC   Protein; auto
TR   HAMAP; MF_04207; -; 1; level=0
XX
Names: BETA_CORONA_HE
XX
ID   HEMA
DE   RecName: Full=Hemagglutinin-esterase;
DE            Short=HE protein;
DE            EC=3.1.1.53;
DE   AltName: Full=E3 glycoprotein;
DE   Flags: Precursor;
GN   Name=HE;
XX
CC   -!- FUNCTION: Structural protein that makes short spikes at the surface of
CC       the virus. Contains receptor binding and receptor-destroying
CC       activities. Mediates de-O-acetylation of N-acetyl-4-O-acetylneuraminic
CC       acid, which is probably the receptor determinant recognized by the
CC       virus on the surface of erythrocytes and susceptible cells. This
CC       receptor-destroying activity is important for virus release as it
CC       probably helps preventing self-aggregation and ensures the efficient
CC       spread of the progeny virus from cell to cell. May serve as a secondary
CC       viral attachment protein for initiating infection, the spike protein
CC       being the major one. May become a target for both the humoral and the
CC       cellular branches of the immune system.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=H2O + N-acetyl-9-O-acetylneuraminate = acetate + H(+) + N-
CC         acetylneuraminate; Xref=Rhea:RHEA:22600, ChEBI:CHEBI:15377,
CC         ChEBI:CHEBI:15378, ChEBI:CHEBI:28999, ChEBI:CHEBI:30089,
CC         ChEBI:CHEBI:35418; EC=3.1.1.53;
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=H2O + N-acetyl-4-O-acetylneuraminate = acetate + H(+) + N-
CC         acetylneuraminate; Xref=Rhea:RHEA:25564, ChEBI:CHEBI:15377,
CC         ChEBI:CHEBI:15378, ChEBI:CHEBI:29006, ChEBI:CHEBI:30089,
CC         ChEBI:CHEBI:35418; EC=3.1.1.53;
CC   -!- SUBUNIT: Homodimer; disulfide-linked. Forms a complex with the M
CC       protein in the pre-Golgi. Associates then with S-M complex to form a
CC       ternary complex S-M-HE.
CC   -!- SUBCELLULAR LOCATION: Virion membrane; Single-pass type I membrane
CC       protein. Host cell membrane; Single-pass type I membrane protein.
CC       Note=In infected cells becomes incorporated into the envelope of
CC       virions during virus assembly at the endoplasmic reticulum and cis
CC       Golgi. However, some may escape incorporation into virions and
CC       subsequently migrate to the cell surface.
CC   -!- PTM: N-glycosylated in the host RER.
CC   -!- SIMILARITY: Belongs to the influenza type C/coronaviruses
CC       hemagglutinin-esterase family.
XX
DR   PROSITE; PS00001; ASN_GLYCOSYLATION; 0-unlimited; trigger=yes
DR   Pfam; PF03996; Hema_esterase; 1; trigger=no
DR   Pfam; PF02710; Hema_HEFG; 1; trigger=no
DR   General; Signal; -; 1; trigger=no
DR   General; Transmembrane; -; 1; trigger=no
XX
KW   Disulfide bond
KW   Glycoprotein
KW   Hemagglutinin
KW   Host cell membrane
KW   Host membrane
KW   Hydrolase
KW   Membrane
KW   Signal
KW   Transmembrane
KW   Transmembrane helix
KW   Viral envelope protein
KW   Virion
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GO   GO:0020002; C:host cell plasma membrane
GO   GO:0016020; C:membrane
GO   GO:0019031; C:viral envelope
GO   GO:0055036; C:virion membrane
GO   GO:0046789; F:host cell surface receptor binding
GO   GO:0001681; F:sialate O-acetylesterase activity
GO   GO:0019064; P:fusion of virus membrane with host plasma membrane
XX
FT   From: HEMA_CVMS (P31614)
FT   SIGNAL          Nter..22
FT   CHAIN           23..Cter
FT                   /note="Hemagglutinin-esterase"
FT   TOPO_DOM        23..407
FT                   /note="Virion surface"
FT   TRANSMEM        408..428
FT                   /note="Helical"
FT   TOPO_DOM        429..Cter
FT                   /note="Intravirion"
FT   REGION          12..132
FT                   /note="Esterase domain 1"
FT   REGION          133..281
FT                   /note="Receptor binding"
FT   REGION          282..395
FT                   /note="Esterase domain 2"
FT   ACT_SITE        45
FT                   /note="Nucleophile"
FT   Condition: S
FT   ACT_SITE        342
FT                   /note="Charge relay system"
FT   Condition: D
FT   ACT_SITE        345
FT                   /note="Charge relay system"
FT   Condition: H
FT   DISULFID        49..70
FT   Condition: C-x*-C
FT   DISULFID        118..167
FT   Condition: C-x*-C
FT   DISULFID        202..291
FT   Condition: C-x*-C
FT   DISULFID        210..264
FT   Condition: C-x*-C
FT   DISULFID        322..327
FT   Condition: C-x*-C
FT   DISULFID        363..387
FT   Condition: C-x*-C
FT   DISULFID        400
FT                   /note="Interchain"
FT   Condition: C-x*-C
XX
Size: 385-439;
Related: None;
Template: P31614;
Scope:
 Viruses; Betacoronavirus
Fusion:
 Nter: None
 Cter: None
Duplicate: None
Plasmid: None
Comments: None
XX
# Revision 1.5 2022/09/29
//