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Angular Mapping of Protein Structure Using Nonlinear Optical Measurements.

ABSTRACT: Proteins are inherently dynamic, flexible molecules that execute precise conformational changes to perform their functions, but existing techniques to directly measure relevant structural changes in solution at room temperature remain limited. Here, we demonstrate a structural technique using second-harmonic generation and two-photon fluorescence under single-laser excitation to map both the mean angular orientation and the distribution width of a probe at various sites throughout the protein with high sensitivity. Our work resolves distinct dihydrofolate reductase (DHFR) ligand-protein conformations, allows interrogation of regions unresolvable by other techniques, and reveals structural differences between DHFR and a point mutant (DHFR-G121V). The technique, angular mapping of protein structure, enables direct and rapid determination of previously unseen aspects of protein structure in a benchtop optical system.

SUBMITTER: Clancy B

PROVIDER: S-EPMC6697465 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Angular Mapping of Protein Structure Using Nonlinear Optical Measurements.

Clancy Bason B Moree Ben B Salafsky Joshua J

Biophysical journal 20190711 3

Proteins are inherently dynamic, flexible molecules that execute precise conformational changes to perform their functions, but existing techniques to directly measure relevant structural changes in solution at room temperature remain limited. Here, we demonstrate a structural technique using second-harmonic generation and two-photon fluorescence under single-laser excitation to map both the mean angular orientation and the distribution width of a probe at various sites throughout the protein wi ...[more]

PMID: 31349993

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