7R5O

1.58 A STRUCTURE OF HUMAN APOFERRITIN OBTAINED FROM TITAN KRIOS 2 AT eBIC, DLS UNDER COMMISSIONING SESSION CM26464-2

Summary for 7R5O

• Entry DOI: 10.2210/pdb7r5o/pdb
• EMDB information: 14332
• Descriptor: Ferritin heavy chain, N-terminally processed, SODIUM ION (3 entities in total)
• Functional Keywords: protein standard, metal binding protein
• Biological source: Homo sapiens (human)
• Total number of polymer chains: 24
• Total formula weight: 485797.44

Authors

Clare, D.K. (deposition date: 2022-02-11, release date: 2022-06-22, Last modification date: 2023-07-05)

Primary citation

Sheng, Y.,Harrison, P.J.,Vogirala, V.,Yang, Z.,Strain-Damerell, C.,Frosio, T.,Himes, B.A.,Siebert, C.A.,Zhang, P.,Clare, D.K.
Application of super-resolution and correlative double sampling in cryo-electron microscopy.
Faraday Disc.Chem.Soc, 240:261-276, 2022

PubMed Abstract: Developments in cryo-EM have allowed atomic or near-atomic resolution structure determination to become routine in single particle analysis (SPA). However, near-atomic resolution structures determined using cryo-electron tomography and sub-tomogram averaging (cryo-ET STA) are much less routine. In this paper, we show that collecting cryo-ET STA data using the same conditions as SPA, with both correlated double sampling (CDS) and the super-resolution mode, allowed apoferritin to be reconstructed out to the physical Nyquist frequency of the images. Even with just two tilt series, STA yields an apoferritin map at 2.9 Å resolution. These results highlight the exciting potential of cryo-ET STA in the future of protein structure determination. While processing SPA data recorded in super-resolution mode may yield structures surpassing the physical Nyquist limit, processing cryo-ET STA data in the super-resolution mode gave no additional resolution benefit. We further show that collecting SPA data in the super-resolution mode, with CDS activated, reduces the estimated -factor, leading to a reduction in the number of particles required to reach a target resolution without compromising the data size on disk and the area imaged in SerialEM. However, collecting SPA data in CDS does reduce throughput, given that a similar resolution structure, with a slightly larger -factor, is achievable with optimised parameters for speed in EPU (without CDS).

PubMed: 35938521
DOI: 10.1039/d2fd00049k

Experimental method

ELECTRON MICROSCOPY (1.6 Å)