Structural biology aims to understand how biological molecules function by determining their three-dimensional structures. However, many targets are too flexible, unstable, or complex for traditional techniques like X-ray crystallography. These limitations can slow or even halt progress.

Transmission electron microscopy (TEM) offers powerful solutions to these challenges. Within structural biology, TEM encompasses a range of imaging modes—including cryogenic electron microscopy (cryo-EM), negative staining, and cellular tomography—that together enable researchers to visualize macromolecules, viruses, organelles, and cellular structures at nanometer to near-atomic resolution.

Cryo-EM, in particular, has become a transformative tool by allowing structural biologists to visualize individual particles in frozen, hydrated states. As a cryogenic mode of TEM, it avoids the need for crystallization or staining and supports high-resolution reconstruction of macromolecular assemblies in near-native conformations. Whether imaging purified molecules or cellular sections, TEM technologies provide essential insights into molecular architecture and function.

The Challenge: Many proteins, especially membrane-associated or flexible ones, cannot be crystallized for X-ray analysis.

TEM Solution: Cryo-TEM allows researchers to image these molecules directly in frozen, hydrated form—bypassing the need for crystallization and enabling structure determination of otherwise elusive targets.Vivamus sagittis lacus vel augue laoreet rutrum faucibus dolor auctor. Duis mollis, est non commodo luctus.

The Challenge: Many macromolecules exist in multiple conformations, but traditional methods that average all particles together can obscure these distinct structural states.

TEM Solution: In cryo-EM, sophisticated computational sorting can separate images of particles into different conformational states, allowing individual reconstructions of each. This reveals how molecules change during function.Vivamus sagittis lacus vel augue laoreet rutrum faucibus dolor auctor. Duis mollis, est non commodo luctus.

The Challenge: Massive molecular complexes often defy symmetry assumptions or size limits used in traditional methods.

TEM Solution: Cryo-EM handles large complexes—often in the megadalton range—and can reconstruct asymmetric or irregular structures with high detail, enabling study of entire molecular machines.

The Challenge: Short-lived intermediates or low-population species are easily missed in ensemble measurements.

TEM Solution: High-throughput data collection and particle classification in cryo-EM allow detection and reconstruction of rare or transient molecular states critical for understanding dynamic processes.

The Challenge: Understanding molecular function requires knowledge of spatial organization in situ.

TEM Solution: By imaging ultrathin sections of cells or tissues, TEM reveals how macromolecules, organelles, and complexes are arranged within their native cellular environment—essential for linking molecular structure to biological function.

The Challenge: Poor sample quality can derail high-resolution studies.

TEM Solution: Negative-stain TEM offers rapid, low-resolution imaging to assess particle homogeneity, concentration, and integrity before advancing to cryo-EM, streamlining workflow and improving data quality.

The Challenge: Conventional techniques lack the resolution to resolve subcellular structures and viral architecture.

TEM Solution: Both conventional and cryo-TEM provide high-resolution views of viruses, vesicles, and organelles, revealing structural details that guide functional and biochemical hypotheses.

Cryogenic preparation—used in cryo-TEM—preserves structural integrity by vitrifying samples rapidly in ice. This minimizes damage from vacuum and the electron beam, allowing imaging of fragile biological material.

By avoiding fixation, dehydration, and staining, cryo-TEM captures hydrated samples in near-native states. This helps preserve molecular conformations that more closely reflect their true biological roles.

From isolated macromolecules to entire cells, TEM technologies—including cryo-EM—have redefined what’s possible in structural biology. JEOL USA offers a portfolio of TEM platforms engineered for high-resolution imaging, reproducibility, and ease of use across diverse biological applications.
Explore JEOL’s advanced TEM and cryo-TEM systems to support your next breakthrough in molecular structure and cellular architecture