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Homochiral and racemic MicroED structures of a peptide repeat from the ice-nucleation protein InaZ
The ice-nucleation protein InaZ from Pseudomonas syringae contains a large number of degenerate repeats that span more than a quarter of its sequence and include the segment GSTSTA. Ab initio structures of this repeat segment, resolved to 1.1 Å by microfocus X-ray crystallography and to 0.9 Å by the...
Autores principales: | , , , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
International Union of Crystallography
2019
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6400192/ https://www.ncbi.nlm.nih.gov/pubmed/30867917 http://dx.doi.org/10.1107/S2052252518017621 |
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author | Zee, Chih-Te Glynn, Calina Gallagher-Jones, Marcus Miao, Jennifer Santiago, Carlos G. Cascio, Duilio Gonen, Tamir Sawaya, Michael R. Rodriguez, Jose A. |
author_facet | Zee, Chih-Te Glynn, Calina Gallagher-Jones, Marcus Miao, Jennifer Santiago, Carlos G. Cascio, Duilio Gonen, Tamir Sawaya, Michael R. Rodriguez, Jose A. |
author_sort | Zee, Chih-Te |
collection | PubMed |
description | The ice-nucleation protein InaZ from Pseudomonas syringae contains a large number of degenerate repeats that span more than a quarter of its sequence and include the segment GSTSTA. Ab initio structures of this repeat segment, resolved to 1.1 Å by microfocus X-ray crystallography and to 0.9 Å by the cryo-EM method MicroED, were determined from both racemic and homochiral crystals. The benefits of racemic protein crystals for structure determination by MicroED were evaluated and it was confirmed that the phase restriction introduced by crystal centrosymmetry increases the number of successful trials during the ab initio phasing of the electron diffraction data. Both homochiral and racemic GSTSTA form amyloid-like protofibrils with labile, corrugated antiparallel β-sheets that mate face to back. The racemic GSTSTA protofibril represents a new class of amyloid assembly in which all-left-handed sheets mate with their all-right-handed counterparts. This determination of racemic amyloid assemblies by MicroED reveals complex amyloid architectures and illustrates the racemic advantage in macromolecular crystallography, now with submicrometre-sized crystals. |
format | Online Article Text |
id | pubmed-6400192 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | International Union of Crystallography |
record_format | MEDLINE/PubMed |
spelling | pubmed-64001922019-03-13 Homochiral and racemic MicroED structures of a peptide repeat from the ice-nucleation protein InaZ Zee, Chih-Te Glynn, Calina Gallagher-Jones, Marcus Miao, Jennifer Santiago, Carlos G. Cascio, Duilio Gonen, Tamir Sawaya, Michael R. Rodriguez, Jose A. IUCrJ Research Papers The ice-nucleation protein InaZ from Pseudomonas syringae contains a large number of degenerate repeats that span more than a quarter of its sequence and include the segment GSTSTA. Ab initio structures of this repeat segment, resolved to 1.1 Å by microfocus X-ray crystallography and to 0.9 Å by the cryo-EM method MicroED, were determined from both racemic and homochiral crystals. The benefits of racemic protein crystals for structure determination by MicroED were evaluated and it was confirmed that the phase restriction introduced by crystal centrosymmetry increases the number of successful trials during the ab initio phasing of the electron diffraction data. Both homochiral and racemic GSTSTA form amyloid-like protofibrils with labile, corrugated antiparallel β-sheets that mate face to back. The racemic GSTSTA protofibril represents a new class of amyloid assembly in which all-left-handed sheets mate with their all-right-handed counterparts. This determination of racemic amyloid assemblies by MicroED reveals complex amyloid architectures and illustrates the racemic advantage in macromolecular crystallography, now with submicrometre-sized crystals. International Union of Crystallography 2019-01-24 /pmc/articles/PMC6400192/ /pubmed/30867917 http://dx.doi.org/10.1107/S2052252518017621 Text en © Chih-Te Zee et al. 2019 http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.http://creativecommons.org/licenses/by/4.0/ |
spellingShingle | Research Papers Zee, Chih-Te Glynn, Calina Gallagher-Jones, Marcus Miao, Jennifer Santiago, Carlos G. Cascio, Duilio Gonen, Tamir Sawaya, Michael R. Rodriguez, Jose A. Homochiral and racemic MicroED structures of a peptide repeat from the ice-nucleation protein InaZ |
title | Homochiral and racemic MicroED structures of a peptide repeat from the ice-nucleation protein InaZ |
title_full | Homochiral and racemic MicroED structures of a peptide repeat from the ice-nucleation protein InaZ |
title_fullStr | Homochiral and racemic MicroED structures of a peptide repeat from the ice-nucleation protein InaZ |
title_full_unstemmed | Homochiral and racemic MicroED structures of a peptide repeat from the ice-nucleation protein InaZ |
title_short | Homochiral and racemic MicroED structures of a peptide repeat from the ice-nucleation protein InaZ |
title_sort | homochiral and racemic microed structures of a peptide repeat from the ice-nucleation protein inaz |
topic | Research Papers |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6400192/ https://www.ncbi.nlm.nih.gov/pubmed/30867917 http://dx.doi.org/10.1107/S2052252518017621 |
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