Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

Capsid protein

Gene
N/A
Organism
Escherichia phage Qbeta (Bacteriophage Q-beta)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Capsid protein self-assembles to form an icosahedral capsid with a T=3 symmetry, about 26 nm in diameter, and consisting of 89 capsid proteins dimers (178 capsid proteins) (PubMed:27671640, PubMed:19913556). Involved in viral genome encapsidation through the interaction between a capsid protein dimer and the multiple packaging signals present in the RNA genome (PubMed:8943226, PubMed:27671640). Binding of the capsid proteins to the viral RNA induces a conformational change required for efficient T=3 shell formation (PubMed:19913556). The capsid contains also 1 copy of the A2 maturation protein (PubMed:27671640).3 Publications
Acts as a translational repressor of viral replicase synthesis late in infection. This latter function is the result of capsid protein interaction with an RNA hairpin which contains the replicase ribosome-binding site.1 Publication

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sitei90RNA-binding1 Publication1

GO - Molecular functioni

  • RNA binding Source: UniProtKB
  • structural molecule activity Source: InterPro
  • translation repressor activity Source: UniProtKB

Keywordsi

Molecular functionRNA-binding
Biological processTranslation regulation

Names & Taxonomyi

Protein namesi
Recommended name:
Capsid protein
Short name:
CP
Alternative name(s):
Coat protein
OrganismiEscherichia phage Qbeta (Bacteriophage Q-beta)
Taxonomic identifieri39803 [NCBI]
Taxonomic lineageiVirusesssRNA virusesssRNA positive-strand viruses, no DNA stageLeviviridaeAllolevivirus
Virus hostiEscherichia coli [TaxID: 562]
Proteomesi
  • UP000185268 Componenti: Genome

Subcellular locationi

GO - Cellular componenti

  • T=3 icosahedral viral capsid Source: UniProtKB

Keywords - Cellular componenti

Capsid protein, T=3 icosahedral capsid protein, Virion

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Mutagenesisi33V → A: Decreased RNA-binding to the viral operator and loss of repressor activity. 1 Publication1
Mutagenesisi50T → A: Decreased RNA-binding to the viral operator and loss of repressor activity. 1 Publication1
Mutagenesisi57S → P: Decreased RNA-binding to the viral operator and loss of repressor activity. 1 Publication1
Mutagenesisi60R → C: Decreased RNA-binding to the viral operator and loss of repressor activity. 1 Publication1
Mutagenesisi62N → D: Decreased RNA-binding to the viral operator and loss of repressor activity. 1 Publication1
Mutagenesisi64K → E: Decreased RNA-binding to the viral operator and loss of repressor activity. 1 Publication1
Mutagenesisi90Y → H: Decreased RNA-binding to the viral operator and loss of repressor activity. 1 Publication1
Mutagenesisi96S → L: Decreased RNA-binding to the viral operator and loss of repressor activity. 1 Publication1

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Initiator methionineiRemoved; by host1 Publication
ChainiPRO_00001648462 – 133Capsid proteinAdd BLAST132

Interactioni

Subunit structurei

Homodimer (PubMed:16531233). The homodimers binds to the viral RNA via an operator hairpin, but also to many other RNA sequences in the viral genome; this interaction probably shifts the virus from the replicative to the assembly phase and ensures specific encapsidation of the viral genome (PubMed:8943226, PubMed:16531233).2 Publications

Structurei

Secondary structure

1133
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Beta strandi7 – 12Combined sources6
Turni13 – 16Combined sources4
Beta strandi18 – 27Combined sources10
Turni29 – 31Combined sources3
Beta strandi34 – 37Combined sources4
Helixi43 – 45Combined sources3
Beta strandi48 – 54Combined sources7
Beta strandi62 – 73Combined sources12
Beta strandi78 – 80Combined sources3
Beta strandi87 – 97Combined sources11
Helixi103 – 116Combined sources14
Helixi120 – 126Combined sources7

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1QBEX-ray3.50A/B/C2-133[»]
4L8HX-ray2.40A/B2-133[»]
5KIPelectron microscopy3.70A/B/C1-133[»]
ProteinModelPortaliP03615.
SMRiP03615.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP03615.

Family & Domainsi

Family and domain databases

Gene3Di3.30.380.10. 1 hit.
InterProiView protein in InterPro
IPR002703. Levivir_coat.
IPR015954. Phage_RNA-type_capsid.
PfamiView protein in Pfam
PF01819. Levi_coat. 1 hit.
SUPFAMiSSF55405. SSF55405. 1 hit.

Sequencei

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

P03615-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MAKLETVTLG NIGKDGKQTL VLNPRGVNPT NGVASLSQAG AVPALEKRVT
60 70 80 90 100
VSVSQPSRNR KNYKVQVKIQ NPTACTANGS CDPSVTRQAY ADVTFSFTQY
110 120 130
STDEERAFVR TELAALLASP LLIDAIDQLN PAY
Length:133
Mass (Da):14,254
Last modified:January 23, 2007 - v2
Checksum:i1B7967F0256C31DE
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti23N → D AA sequence (PubMed:5570434).Curated1
Sequence conflicti57Missing AA sequence (PubMed:5570434).Curated1

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural varianti34A → S in strain: Qbeta_3_FR. 1 Publication1
Natural varianti76T → A in strain: QB_1 and Qbeta_1_FR. 2 Publications1

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M99039 Unassigned DNA. Translation: AAA16662.1.
AY099114 Genomic RNA. Translation: AAM33126.1.
GQ153928 Genomic RNA. Translation: ACY07224.1.
GQ153929 Genomic RNA. Translation: ACY07228.1.
GQ153930 Genomic RNA. Translation: ACY07232.1.
GQ153931 Genomic RNA. Translation: ACY07236.1.
JF719735 Genomic RNA. Translation: AEQ25542.1.
JF719736 Genomic RNA. Translation: AEQ25546.1.
JF719737 Genomic RNA. Translation: AEQ25550.1.
AB971354 Genomic RNA. Translation: BAP18764.1.
V00643 mRNA. Translation: CAA23992.1.
PIRiA92240. VCBPQB.

Cross-referencesi

Web resourcesi

Virus Particle ExploreR db

Icosahedral capsid structure

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M99039 Unassigned DNA. Translation: AAA16662.1.
AY099114 Genomic RNA. Translation: AAM33126.1.
GQ153928 Genomic RNA. Translation: ACY07224.1.
GQ153929 Genomic RNA. Translation: ACY07228.1.
GQ153930 Genomic RNA. Translation: ACY07232.1.
GQ153931 Genomic RNA. Translation: ACY07236.1.
JF719735 Genomic RNA. Translation: AEQ25542.1.
JF719736 Genomic RNA. Translation: AEQ25546.1.
JF719737 Genomic RNA. Translation: AEQ25550.1.
AB971354 Genomic RNA. Translation: BAP18764.1.
V00643 mRNA. Translation: CAA23992.1.
PIRiA92240. VCBPQB.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1QBEX-ray3.50A/B/C2-133[»]
4L8HX-ray2.40A/B2-133[»]
5KIPelectron microscopy3.70A/B/C1-133[»]
ProteinModelPortaliP03615.
SMRiP03615.
ModBaseiSearch...
MobiDBiSearch...

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Miscellaneous databases

EvolutionaryTraceiP03615.

Family and domain databases

Gene3Di3.30.380.10. 1 hit.
InterProiView protein in InterPro
IPR002703. Levivir_coat.
IPR015954. Phage_RNA-type_capsid.
PfamiView protein in Pfam
PF01819. Levi_coat. 1 hit.
SUPFAMiSSF55405. SSF55405. 1 hit.
ProtoNetiSearch...

Entry informationi

Entry nameiCAPSD_BPQBE
AccessioniPrimary (citable) accession number: P03615
Secondary accession number(s): D0U1F3, G4WZR7, Q774G0
Entry historyiIntegrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: January 23, 2007
Last modified: March 15, 2017
This is version 90 of the entry and version 2 of the sequence. See complete history.
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programViral Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Direct protein sequencing

Documents

  1. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into one UniRef entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.