REL PDBe PDBe PDBe 2012-08-23 2012-08-29 2012-08-29 2012-08-29 Kumar V Butcher SJ Oorni K Engelhardt P Heikkonen J Kaski K Ala-Korpela M Kovanen PT LDL, native LDL, human body temperature Kumar V Butcher SJ Oorni K Engelhardt P Heikkonen J Kaski K Ala-Korpela M Kovanen PT PLOS ONE 6 e18841 e18841 2011 21573056 doi:10.1371/journal.pone.0018841 LDL at 37C LDL at 37C

Samples were vitrified on Quantifoil holey carbon grids (Quantifoil Micro Tools, GmbH) either at 6C or 37C, allowing pre-equilibration of the sample at the desired temperature for at least 45 minutes prior to plunging.

1 apoB-100 Homo sapiens Human Blood false singleParticle particle 0.3 7.4 ETHANE OTHER FEI TECNAI F20 FLOOD BEAM BRIGHT FIELD FIELD EMISSION GUN 200 OTHER 2005-12-30 ZEISS SCAI 26083

Initially only phase-flipping was carried out to correct for the contrast transfer function. To reduce the effect of image noise and artefacts, an initial single particle reconstruction was made on images de-noised with an information theory [Minimum Description Length (MDL)] based method which we have introduced earlier. Fifty initial class averages were obtained using a reference-free classification of 3000 images by multivariate statistical analysis using parameters, as suggested in EMAN . Angles were assigned using the cross common lines method prior to reconstruction using weighted-back projection. The initial 3D models were low-pass filtered. The 2D image dataset was increased to include all of the particles and iterative refinement continued. After each iteration of the single-particle-reconstruction process only 75% of the images with the highest correlation values were chosen. In order to avoid any bias in 3D reconstruction due to the de-noising, the final reconstructions were made using raw images after being assigned to classes using their de-noised equivalents

Each particle

C1 OTHER 16.0 FSC 0.5 CUT-OFF EMAN 29844

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