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Efficient cellular solid-state NMR of membrane proteins by targeted protein labeling.

ABSTRACT: Solid-state NMR spectroscopy (ssNMR) has made significant progress towards the study of membrane proteins in their native cellular membranes. However, reduced spectroscopic sensitivity and high background signal levels can complicate these experiments. Here, we describe a method for ssNMR to specifically label a single protein by repressing endogenous protein expression with rifampicin. Our results demonstrate that treatment of E. coli with rifampicin during induction of recombinant membrane protein expression reduces background signals for different expression levels and improves sensitivity in cellular membrane samples. Further, the method reduces the amount of time and resources needed to produce membrane protein samples, enabling new strategies for studying challenging membrane proteins by ssNMR.

SUBMITTER: Baker LA

PROVIDER: S-EPMC4451474 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Efficient cellular solid-state NMR of membrane proteins by targeted protein labeling.

Baker Lindsay A LA Daniëls Mark M van der Cruijsen Elwin A W EA Folkers Gert E GE Baldus Marc M

Journal of biomolecular NMR 20150509 2

Solid-state NMR spectroscopy (ssNMR) has made significant progress towards the study of membrane proteins in their native cellular membranes. However, reduced spectroscopic sensitivity and high background signal levels can complicate these experiments. Here, we describe a method for ssNMR to specifically label a single protein by repressing endogenous protein expression with rifampicin. Our results demonstrate that treatment of E. coli with rifampicin during induction of recombinant membrane pro ...[more]

PMID: 25956570

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