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Imaging proteins at the single-molecule level.

ABSTRACT: Imaging single proteins has been a long-standing ambition for advancing various fields in natural science, as for instance structural biology, biophysics, and molecular nanotechnology. In particular, revealing the distinct conformations of an individual protein is of utmost importance. Here, we show the imaging of individual proteins and protein complexes by low-energy electron holography. Samples of individual proteins and protein complexes on ultraclean freestanding graphene were prepared by soft-landing electrospray ion beam deposition, which allows chemical- and conformational-specific selection and gentle deposition. Low-energy electrons do not induce radiation damage, which enables acquiring subnanometer resolution images of individual proteins (cytochrome C and BSA) as well as of protein complexes (hemoglobin), which are not the result of an averaging process.

SUBMITTER: Longchamp JN

PROVIDER: S-EPMC5321008 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Imaging proteins at the single-molecule level.

Longchamp Jean-Nicolas JN Rauschenbach Stephan S Abb Sabine S Escher Conrad C Latychevskaia Tatiana T Kern Klaus K Fink Hans-Werner HW

Proceedings of the National Academy of Sciences of the United States of America 20170113 7

Imaging single proteins has been a long-standing ambition for advancing various fields in natural science, as for instance structural biology, biophysics, and molecular nanotechnology. In particular, revealing the distinct conformations of an individual protein is of utmost importance. Here, we show the imaging of individual proteins and protein complexes by low-energy electron holography. Samples of individual proteins and protein complexes on ultraclean freestanding graphene were prepared by s ...[more]

PMID: 28087691

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