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Analysis of SMALP co-extracted phospholipids shows distinct membrane environments for three classes of bacterial membrane protein.

ABSTRACT: Biological characterisation of membrane proteins lags behind that of soluble proteins. This reflects issues with the traditional use of detergents for extraction, as the surrounding lipids are generally lost, with adverse structural and functional consequences. In contrast, styrene maleic acid (SMA) copolymers offer a detergent-free method for biological membrane solubilisation to produce SMA-lipid particles (SMALPs) containing membrane proteins together with their surrounding lipid environment. We report the development of a reverse-phase LC-MS/MS method for bacterial phospholipids and the first comparison of the profiles of SMALP co-extracted phospholipids from three exemplar bacterial membrane proteins with different topographies: FtsA (associated membrane protein), ZipA (single transmembrane helix), and PgpB (integral membrane protein). The data showed that while SMA treatment per se did not preferentially extract specific phospholipids from the membrane, SMALP-extracted ZipA showed an enrichment in phosphatidylethanolamines and depletion in cardiolipins compared to the bulk membrane lipid. Comparison of the phospholipid profiles of the 3 SMALP-extracted proteins revealed distinct lipid compositions for each protein: ZipA and PgpB were similar, but in FtsA samples longer chain phosphatidylglycerols and phosphatidylethanolamines were more abundant. This method offers novel information on the phospholipid interactions of these membrane proteins.

SUBMITTER: Teo ACK

PROVIDER: S-EPMC6372662 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Analysis of SMALP co-extracted phospholipids shows distinct membrane environments for three classes of bacterial membrane protein.

Teo Alvin C K ACK Lee Sarah C SC Pollock Naomi L NL Stroud Zoe Z Hall Stephen S Thakker Alpesh A Pitt Andrew R AR Dafforn Timothy R TR Spickett Corinne M CM Roper David I DI

Scientific reports 20190212 1

Biological characterisation of membrane proteins lags behind that of soluble proteins. This reflects issues with the traditional use of detergents for extraction, as the surrounding lipids are generally lost, with adverse structural and functional consequences. In contrast, styrene maleic acid (SMA) copolymers offer a detergent-free method for biological membrane solubilisation to produce SMA-lipid particles (SMALPs) containing membrane proteins together with their surrounding lipid environment. ...[more]

PMID: 30755655

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Dataset Information

Analysis of SMALP co-extracted phospholipids shows distinct membrane environments for three classes of bacterial membrane protein.

Publications

Analysis of SMALP co-extracted phospholipids shows distinct membrane environments for three classes of bacterial membrane protein.

Similar Datasets

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