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Protein structure. Engineering of a superhelicase through conformational control.

ABSTRACT: Conformational control of biomolecular activities can reveal functional insights and enable the engineering of novel activities. Here we show that conformational control through intramolecular cross-linking of a helicase monomer with undetectable unwinding activity converts it into a superhelicase that can unwind thousands of base pairs processively, even against a large opposing force. A natural partner that enhances the helicase activity is shown to achieve its stimulating role also by selectively stabilizing the active conformation. Our work provides insight into the regulation of nucleic acid unwinding activity and introduces a monomeric superhelicase without nuclease activities, which may be useful for biotechnological applications.

SUBMITTER: Arslan S

PROVIDER: S-EPMC4417355 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Protein structure. Engineering of a superhelicase through conformational control.

Arslan Sinan S Khafizov Rustem R Thomas Christopher D CD Chemla Yann R YR Ha Taekjip T

Science (New York, N.Y.) 20150401 6232

Conformational control of biomolecular activities can reveal functional insights and enable the engineering of novel activities. Here we show that conformational control through intramolecular cross-linking of a helicase monomer with undetectable unwinding activity converts it into a superhelicase that can unwind thousands of base pairs processively, even against a large opposing force. A natural partner that enhances the helicase activity is shown to achieve its stimulating role also by selecti ...[more]

PMID: 25883358

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