View in EDS

Affinity tags can reduce merohedral twinning of membrane protein crystals.

Saved in:
Bibliographic Details
Title: Affinity tags can reduce merohedral twinning of membrane protein crystals.
Authors: Backmark, Anna1, Nyblom, Maria1, Törnroth-Horsefield, Susanna2, Kosinska-Eriksson, Urszula2, Nordén, Kristina3, Fellert, Maria3, Kjellbom, Per3, Johanson, Urban3, Hedfalk, Kristina2, Lindkvist-Petersson, Karin4, Neutze, Richard2, Horsefield, Rob2 rob@chem.gu.se
Source: Acta Crystallographica: Section D (Wiley-Blackwell). Nov2008, Vol. 64 Issue 11, p1183-1186. 4p. 1 Diagram, 1 Chart.
Subjects: Crystals, Membrane proteins, Aquaporins, Protein affinity labeling, Twinning (Crystallography)
Abstract: This work presents a comparison of the crystal packing of three eukaryotic membrane proteins: human aquaporin 1, human aquaporin 5 and a spinach plasma membrane aquaporin. All were purified from expression constructs both with and without affinity tags. With the exception of tagged aquaporin 1, all constructs yielded crystals. Two significant effects of the affinity tags were observed: crystals containing a tag typically diffracted to lower resolution than those from constructs encoding the protein sequence alone and constructs without a tag frequently produced crystals that suffered from merohedral twinning. Twinning is a challenging crystallographic problem that can seriously hinder solution of the structure. Thus, for integral membrane proteins, the addition of an affinity tag may help to disrupt the approximate symmetry of the protein and thereby reduce or avoid merohedral twinning. [ABSTRACT FROM AUTHOR]
Copyright of Acta Crystallographica: Section D (Wiley-Blackwell) is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:This work presents a comparison of the crystal packing of three eukaryotic membrane proteins: human aquaporin 1, human aquaporin 5 and a spinach plasma membrane aquaporin. All were purified from expression constructs both with and without affinity tags. With the exception of tagged aquaporin 1, all constructs yielded crystals. Two significant effects of the affinity tags were observed: crystals containing a tag typically diffracted to lower resolution than those from constructs encoding the protein sequence alone and constructs without a tag frequently produced crystals that suffered from merohedral twinning. Twinning is a challenging crystallographic problem that can seriously hinder solution of the structure. Thus, for integral membrane proteins, the addition of an affinity tag may help to disrupt the approximate symmetry of the protein and thereby reduce or avoid merohedral twinning. [ABSTRACT FROM AUTHOR]
ISSN:09074449
DOI:10.1107/S090744490802948X