• Issue

    Acta Crystallographica Section D: Volume 81, Issue 4

    147-211
    April 2025

research papers

Open Access

InstaMap: instant-NGP for cryo-EM density maps

  • Pages: 147-169
  • First Published: 03 April 2025
InstaMap: instant-NGP for cryo-EM density maps

Cryo-EM density-map inference, with fixed pose and contrast transfer function, using a multi-resolution hash-encoding framework called instant-NGP, is described, together with its extension to heterogeneity inference by bending space with a per-image vector field.

Open Access

Duplicate entries in the Protein Data Bank: how to detect and handle them

  • Pages: 170-180
  • First Published: 17 March 2025
Duplicate entries in the Protein Data Bank: how to detect and handle them

A global analysis of protein crystal structures in the Protein Data Bank (PDB) reveals many pairs with (nearly) identical main-chain coordinates. Such cases are identified and analyzed, leading to a proposal about how the PDB could ameliorate this problem.

Structural basis for the fast maturation of pcStar, a photoconvertible fluorescent protein

  • Pages: 181-195
  • First Published: 17 March 2025
Structural basis for the fast maturation of pcStar, a photoconvertible fluorescent protein

X-ray diffraction analysis and molecular-dynamics simulations of two photoconvertible fluorescent proteins, mEos3.2 and pcStar, were performed in their green states to elucidate possible mechanisms underlying the enhancement of the optical properties of pcStar compared with mEos3.2, with the purpose of obtaining a higher maturation rate and brighter fluorescence emission.

Restoration of the 3D structure of insect flight muscle from a rotationally averaged 2D X-ray diffraction pattern

  • Pages: 196-206
  • First Published: 03 April 2025
Restoration of the 3D structure of insect flight muscle from a rotationally averaged 2D X-ray diffraction pattern

By extending the principle of coherent diffractive imaging, we have developed a technique to restore the 3D fine structure of insect flight muscle from its rotationally averaged 2D X-ray diffraction pattern. The restoration was performed not only in silico but also in calculations using a recorded diffraction pattern.

obituaries

Jan Drenth (1925–2025)

  • Pages: 207-211
  • First Published: 03 April 2025
Jan Drenth (1925–2025)

Jan Drenth is remembered.