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Nano-scale alignment of proteins on a flexible DNA backbone.

ABSTRACT: Nano-scale alignment of several proteins with freedom of motion is equivalent to an enormous increase in effective local concentration of proteins and will enable otherwise impossible weak and/or cooperative associations between them or with their ligands. For this purpose, a DNA backbone made of six oligodeoxynucleotide (ODN) chains is designed in which five double-stranded segments are connected by four single-stranded flexible linkers. A desired protein with an introduced cysteine is connected covalently to the 5'-end of azido-ODN by catalyst-free click chemistry. Then, six protein-ODN conjugates are assembled with their complementary nucleotide sequences into a single multi-protein-DNA complex, and six proteins are aligned along the DNA backbone. Flexible alignment of proteins is directly observed by high-speed AFM imaging, and association of proteins with weak interaction is demonstrated by fluorescence resonance energy transfer between aligned proteins.

SUBMITTER: Nojima T

PROVIDER: S-EPMC3530504 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Nano-scale alignment of proteins on a flexible DNA backbone.

Nojima Tatsuya T Konno Hiroki H Kodera Noriyuki N Seio Kohji K Taguchi Hideki H Yoshida Masasuke M

PloS one 20121226 12

Nano-scale alignment of several proteins with freedom of motion is equivalent to an enormous increase in effective local concentration of proteins and will enable otherwise impossible weak and/or cooperative associations between them or with their ligands. For this purpose, a DNA backbone made of six oligodeoxynucleotide (ODN) chains is designed in which five double-stranded segments are connected by four single-stranded flexible linkers. A desired protein with an introduced cysteine is connecte ...[more]

PMID: 23300700

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