23WI | PDB 000023WI: Subtomogram Average of the 70S Ribosome

What is 23WI?

The PDB entry was deposited on February 23, 2026 and released on July 15, 2026. The associated experimental electron microscopy density map is identified as EMD-67081.

23WI Structure Summary

23WI and the 70S Ribosome

The central structure represented by 23WI is the bacterial 70S ribosome. Ribosomes are large ribonucleoprotein complexes responsible for translating messenger RNA into proteins.

In bacteria such as Escherichia coli, the 70S ribosome consists of two major subunits:

Together, these two subunits form the functional bacterial 70S ribosome.

Subtomogram Averaging in PDB 23WI

A defining feature of 23WI is the use of subtomogram averaging.

Subtomogram averaging is an electron microscopy image-processing approach used to improve the structural information obtained from multiple copies of the same macromolecular complex. Individual subtomograms can contain noise and incomplete information.

By aligning and averaging multiple related observations, researchers can improve the signal-to-noise ratio and reconstruct a more detailed molecular structure.

For the 23WI structure, subtomogram averaging was used to reconstruct the E. coli 70S ribosome from electron microscopy data.

Cryo-EM and the CRYO ARM 300II

The experimental data associated with 23WI were obtained using electron microscopy, with the structure described as a subtomogram average using the CRYO ARM 300II.

The CRYO ARM 300II is a high-performance transmission electron microscope designed for cryogenic electron microscopy applications. Instruments in this class enable researchers to examine biological macromolecules at very high resolution while preserving samples in a near-native frozen state.

Cryo-EM has become an important structural biology technique for investigating proteins, nucleic acids, ribosomes, viruses, membrane complexes, and other large molecular assemblies.

Why the 23WI Structure Matters

The 23WI PDB entry is useful for researchers interested in bacterial translation, ribosome structure, structural biology, and cryo-electron microscopy.

23WI and Escherichia coli

Both the source organism and expression system associated with 23WI are Escherichia coli.

E. coli is one of the most extensively studied bacterial model organisms in molecular biology. Its ribosome has therefore been investigated using biochemical, genetic, structural, and computational approaches.

The availability of a high-resolution 70S ribosome structure such as 23WI provides another resource for examining the molecular architecture of the E. coli translation machinery.

The PDB record indicates no mutations for this entry.

Experimental Data for 23WI

23WI and EMDB Entry EMD-67081

The structural coordinates and electron microscopy reconstruction represent complementary resources.

The 23WI PDB entry provides the deposited structural model, while EMD-67081 corresponds to the associated electron microscopy density map.

23WI PDB DOI and Database Resources

The official DOI associated with the structure is available through the Protein Data Bank.

Explore 23WI in the Molecular Structure Explorer

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23WI Authors and Funding

The deposition authors associated with 23WI are:

• Yanagisawa, H.
• Makino, F.
• Eisenstein, F.
• Miyata, T.
• Kinoshita, M.
• Kikkawa, M.
• Namba, K.

The work was supported by the Japan Agency for Medical Research and Development (AMED).

Frequently Asked Questions About 23WI

Conclusion

23WI | PDB 000023WI represents a high-resolution structural study of the 70S ribosome from Escherichia coli. Generated using electron microscopy and subtomogram averaging, the structure has a reported 2.60 Å resolution and is associated with the EM density map EMD-67081.

For researchers studying ribosome architecture, bacterial translation, cryo-EM, structural bioinformatics, or macromolecular complexes, PDB 23WI provides a valuable structural reference.