[English] 日本語
Yorodumi
- EMDB-56100: gp39 protein from Escherichia phage vB_EcoS_NBD2, unbent tubule, ... -

+
Open data


ID or keywords:

Loading...

-
Basic information

Entry
Database: EMDB / ID: EMD-56100
Titlegp39 protein from Escherichia phage vB_EcoS_NBD2, unbent tubule, focused map 1
Map dataUnsharpened local refinement map obtained with a mask covering the central gp39 hexamer
Sample
  • Complex: gp39 protein from Escherichia phage vB_EcoS_NBD2
KeywordsEscherichia phage vB_EcoS_NBD2 / bacteriophage tail / VIRAL PROTEIN
Biological speciesEscherichia phage vB_EcoS_NBD2 (virus)
Methodsingle particle reconstruction / cryo EM / Resolution: 3.11 Å
AuthorsSasnauskas G / Tamulaitiene G / Poviloniene S / Casaite V / Meskys R
Funding supportLithuania, 1 items
OrganizationGrant numberCountry
Research Council of LithuaniaLithuania
CitationJournal: Protein Sci / Year: 2026
Title: The Lord of the Rings: Cysteine bonds crosslink the tail of siphovirus.
Authors: Simona Povilonienė / Giedrius Sasnauskas / Giedrė Tamulaitienė / Greta Labutytė / Martynas Talaikis / Algirdas Mikšys / Aurelija Zajančkauskaitė / Lidija Truncaitė / Rolandas Meškys / Vida Časaitė
Abstract: Long, non-contractile tails composed of helical hexameric protein repeats that assemble into continuous tubular structures characterize siphoviruses. The siphovirus tail tube protein gp39 contains ...Long, non-contractile tails composed of helical hexameric protein repeats that assemble into continuous tubular structures characterize siphoviruses. The siphovirus tail tube protein gp39 contains two cysteine residues per monomer. Cryo-electron microscopy revealed that these cysteines are oriented toward the interface between the rings, which facilitates the formation of inter-ring disulfide bonds. Phylogenetic analysis revealed that in the phage tail tube protein-3 (PF08813) family, only a single branch, representing approximately 14% of its members, contains disulfide bonds within the tubular structure, indicating a clear evolutionary adaptation to stabilize the structure. Structural characterization of gp39 alongside its homolog gp13, which naturally lacks disulfide crosslinks, provided insight into this stabilization strategy. Both gp39 and gp13 can self-assemble into tubular structures independently of disulfide bond formation. When cysteine residues were inserted into gp13 at the same positions as in gp39, disulfide bonds were formed, as confirmed by Raman spectroscopy. Differential scanning fluorimetry further demonstrated that variants containing disulfide bonds exhibit enhanced thermal stability. These results reveal the evolutionary and structural basis by which disulfide bonds ensure the stability of phage tail structures and establish the fundamental principles for the design of robust, thermally stable protein nanotubes.
History
DepositionDec 17, 2025-
Header (metadata) releaseSep 23, 2026-
Map releaseSep 23, 2026-
UpdateSep 23, 2026-
Current statusSep 23, 2026Processing site: PDBe / Status: Released

-
Structure visualization

Supplemental images

emd_56100.png

Downloads & links

-
Map

FileDownload / File: emd_56100.map.gz / Format: CCP4 / Size: 52.7 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES)
AnnotationUnsharpened local refinement map obtained with a mask covering the central gp39 hexamer
Projections & slices

Image control

Size
Brightness
Contrast
Others
AxesZ (Sec.)Y (Row.)X (Col.)
1.1 Å/pix.
x 240 pix.
= 264. Å		1.1 Å/pix.
x 240 pix.
= 264. Å		1.1 Å/pix.
x 240 pix.
= 264. Å

Surface

Projections

Slices (1/3)

Slices (1/2)

Slices (2/3)

Images are generated by Spider.

Voxel sizeX=Y=Z: 1.1 Å
Density

Histogram

Histogram (log scale)
Contour LevelBy AUTHOR: 0.12
Minimum - Maximum-0.16459693 - 0.42449164
Average (Standard dev.)0.0030500668 (±0.016569247)
SymmetrySpace group: 1
Details

EMDB XML:

Map geometry
Axis orderXYZ
Origin000
Dimensions240240240
Spacing240240240
CellA=B=C: 264.0 Å
α=β=γ: 90.0 °

-
Supplemental data

-
Mask #1

Fileemd_56100_msk_1.map
Projections & Slices
AxesZYX

Projections

Slices (1/2)
Density Histograms

Histogram

Histogram (log scale)

-
Half map: #2

Fileemd_56100_half_map_1.map
Projections & Slices
AxesZYX

Projections

Slices (1/2)
Density Histograms

Histogram

Histogram (log scale)

-
Half map: #1

Fileemd_56100_half_map_2.map
Projections & Slices
AxesZYX

Projections

Slices (1/2)
Density Histograms

Histogram

Histogram (log scale)

-
Sample components

-
Entire : gp39 protein from Escherichia phage vB_EcoS_NBD2

EntireName: gp39 protein from Escherichia phage vB_EcoS_NBD2
Components
  • Complex: gp39 protein from Escherichia phage vB_EcoS_NBD2

-
Supramolecule #1: gp39 protein from Escherichia phage vB_EcoS_NBD2

SupramoleculeName: gp39 protein from Escherichia phage vB_EcoS_NBD2 / type: complex / ID: 1 / Parent: 0 / Macromolecule list: #1
Source (natural)Organism: Escherichia phage vB_EcoS_NBD2 (virus)

-
Experimental details

-
Structure determination

Methodcryo EM
Processingsingle particle reconstruction
Aggregation stateparticle

-
Sample preparation

BufferpH: 8
GridModel: Quantifoil R1.2/1.3 / Material: COPPER / Mesh: 300 / Pretreatment - Type: GLOW DISCHARGE
VitrificationCryogen name: ETHANE / Chamber humidity: 95 % / Chamber temperature: 277 K / Instrument: FEI VITROBOT MARK IV

-
Electron microscopy

MicroscopeTFS GLACIOS
SoftwareName: EPU (ver. 3.0)
Image recordingFilm or detector model: FEI FALCON III (4k x 4k) / Detector mode: COUNTING / Number grids imaged: 1 / Number real images: 890 / Average electron dose: 30.0 e/Å2
Electron beamAcceleration voltage: 200 kV / Electron source: FIELD EMISSION GUN
Electron opticsIllumination mode: OTHER / Imaging mode: BRIGHT FIELD / Nominal defocus max: 2.0 µm / Nominal defocus min: 1.0 µm

+
Image processing

CTF correctionSoftware - Name: cryoSPARC / Type: PHASE FLIPPING AND AMPLITUDE CORRECTION
Startup modelType of model: INSILICO MODEL
Final reconstructionApplied symmetry - Point group: C6 (6 fold cyclic) / Resolution.type: BY AUTHOR / Resolution: 3.11 Å / Resolution method: FSC 0.143 CUT-OFF / Software - Name: cryoSPARC (ver. 4.7.1) / Number images used: 73243
Initial angle assignmentType: NOT APPLICABLE
Final angle assignmentType: MAXIMUM LIKELIHOOD
FSC plot (resolution estimation)

-
Atomic model buiding 1

Initial modelChain - Source name: AlphaFold / Chain - Initial model type: in silico model
SoftwareName: UCSF ChimeraX (ver. 1.7)

+
About Yorodumi

-
News

-
Feb 9, 2022. New format data for meta-information of EMDB entries

New format data for meta-information of EMDB entries

  • Version 3 of the EMDB header file is now the official format.
  • The previous official version 1.9 will be removed from the archive.

Related info.:EMDB header

External links:wwPDB to switch to version 3 of the EMDB data model

-
Aug 12, 2020. Covid-19 info

Covid-19 info

URL: https://pdbj.org/emnavi/covid19.php

New page: Covid-19 featured information page in EM Navigator.

Related info.:Covid-19 info / Mar 5, 2020. Novel coronavirus structure data

+
Mar 5, 2020. Novel coronavirus structure data

Novel coronavirus structure data

Related info.:Yorodumi Speices / Aug 12, 2020. Covid-19 info

External links:COVID-19 featured content - PDBj / Molecule of the Month (242)：Coronavirus Proteases

+
Jan 31, 2019. EMDB accession codes are about to change! (news from PDBe EMDB page)

EMDB accession codes are about to change! (news from PDBe EMDB page)

  • The allocation of 4 digits for EMDB accession codes will soon come to an end. Whilst these codes will remain in use, new EMDB accession codes will include an additional digit and will expand incrementally as the available range of codes is exhausted. The current 4-digit format prefixed with “EMD-” (i.e. EMD-XXXX) will advance to a 5-digit format (i.e. EMD-XXXXX), and so on. It is currently estimated that the 4-digit codes will be depleted around Spring 2019, at which point the 5-digit format will come into force.
  • The EM Navigator/Yorodumi systems omit the EMD- prefix.

Related info.:Q: What is EMD? / ID/Accession-code notation in Yorodumi/EM Navigator

External links:EMDB Accession Codes are Changing Soon! / Contact to PDBj

+
Jul 12, 2017. Major update of PDB

Major update of PDB

  • wwPDB released updated PDB data conforming to the new PDBx/mmCIF dictionary.
  • This is a major update changing the version number from 4 to 5, and with Remediation, in which all the entries are updated.
  • In this update, many items about electron microscopy experimental information are reorganized (e.g. em_software).
  • Now, EM Navigator and Yorodumi are based on the updated data.

External links:wwPDB Remediation / Enriched Model Files Conforming to OneDep Data Standards Now Available in the PDB FTP Archive

-
Yorodumi

Thousand views of thousand structures

  • Yorodumi is a browser for structure data from EMDB, PDB, SASBDB, etc.
  • This page is also the successor to EM Navigator detail page, and also detail information page/front-end page for Omokage search.
  • The word "yorodu" (or yorozu) is an old Japanese word meaning "ten thousand". "mi" (miru) is to see.

Related info.:EMDB / PDB / SASBDB / Comparison of 3 databanks / Yorodumi Search / Aug 31, 2016. New EM Navigator & Yorodumi / Yorodumi Papers / Jmol/JSmol / Function and homology information / Changes in new EM Navigator and Yorodumi

Read more