Exploring the in meso crystallization mechanism by characterizing the lipid mesophase microenvironment during the growth of single transmembrane alpha-helical peptide crystals

van &#39;t Hag, L; Knoblich, K; Seabrook, SA; Kirby, NM; Mudie, ST; Lau, D; Li, X; Gras, SL; Mulet, X; Call, ME; Call, MJ; Drummond, CJ; Conn, CE

Author(s): van 't Hag, L; Knoblich, K; Seabrook, SA; Kirby, NM; Mudie, ST; Lau, D; Li, X; Gras, SL; Mulet, X; Call, ME; Call, MJ; Drummond, CJ; Conn, CE;
Details: Publication Year 2016-07-28,Volume 374,Issue #2072,Page pii: 20150125.
Journal Title: Philos Trans A Math Phys Eng Sci
Publication Type: Journal Article
Abstract: The proposed mechanism for in meso crystallization of transmembrane proteins suggests that a protein or peptide is initially uniformly dispersed in the lipid self-assembly cubic phase but that crystals grow from a local lamellar phase, which acts as a conduit between the crystal and the bulk cubic phase. However, there is very limited experimental evidence for this theory. We have developed protocols to investigate the lipid mesophase microenvironment during crystal growth using standard procedures readily available in crystallography laboratories. This technique was used to characterize the microenvironment during crystal growth of the DAP12-TM peptide using synchrotron small angle X-ray scattering (SAXS) with a micro-sized X-ray beam. Crystal growth was found to occur from the gyroid cubic mesophase. For one in four crystals, a highly oriented local lamellar phase was observed, providing supporting evidence for the proposed mechanism for in meso crystallization. A new observation of this study was that we can differentiate diffraction peaks from crystals grown in meso, from peaks originating from the surrounding lipid matrix, potentially opening up the possibility of high-throughput SAXS analysis of in meso grown crystals.This article is part of the themed issue 'Soft interfacial materials: from fundamentals to formulation'.
Publisher: Royal Society Pub
Research Division(s): Structural Biology
PubMed ID: 27298442
Publisher's Version: https://doi.org/10.1098/rsta.2015.0125
NHMRC Grants: NHMRC/1011352,
ARC Grants: ARC/FT120100145,
Terms of Use/Rights Notice: Refer to copyright notice on published article.

Creation Date: 2016-06-17 03:01:36

Last Modified: 2016-06-17 03:10:52