TY - JOUR
T1 - A hinge migration mechanism unlocks the evolution of green-to-red photoconversion in GFP-like proteins
AU - Kim, Hanseong
AU - Zou, Taisong
AU - Modi, Chintan
AU - Dörner, Katerina
AU - Grunkemeyer, Timothy J.
AU - Chen, Liqing
AU - Fromme, Raimund
AU - Matz, Mikhail V.
AU - Ozkan, Sefika
AU - Wachter, Rebekka
N1 - Funding Information:
This work was supported by NSF Award MCB-0615938 (to R.M.W.) and by NIH Award U54 GM094599 (to R.M.W. and S.B.O.). Crystallographic data were collected at the Advanced Light Source (ALS) beamlines 4.2.2, 8.2.1, and 8.2.2 and at the Advanced Photon Source (APS) beamline 19 ID. ALS is supported by the US Department of Energy (DOE) under Contract DE-AC02-05CH11231 . The Argonne National Laboratory at APS is operated by the University of Chicago Argonne for the US DOE Office of Biological and Environmental Research under Contract DE-AC02-06CH11357 .
Publisher Copyright:
© 2015 Elsevier Ltd. All rights reserved.
PY - 2015/1/6
Y1 - 2015/1/6
N2 - In proteins, functional divergence involves mutations that modify structure and dynamics. Here we provide experimental evidence for an evolutionary mechanism driven solely by long-range dynamic motions without significant backbone adjustments, catalytic group rearrangements, or changes in subunit assembly. Crystallographic structures were determined for several reconstructed ancestral proteins belonging to a GFP class frequently employed in superresolution microscopy. Their chain flexibility was analyzed using molecular dynamics and perturbation response scanning. The green-to-red photoconvertible phenotype appears to have arisen from a common green ancestor by migration of a knob-like anchoring region away from the active site diagonally across the β barrel fold. The allosterically coupled mutational sites provide active site conformational mobility via epistasis. We propose that light-induced chromophore twisting is enhanced in a reverse-protonated subpopulation, activating internal acid-base chemistry and backbone cleavage to enlarge the chromophore. Dynamics-driven hinge migration may represent a more general platform for the evolution of novel enzyme activities.
AB - In proteins, functional divergence involves mutations that modify structure and dynamics. Here we provide experimental evidence for an evolutionary mechanism driven solely by long-range dynamic motions without significant backbone adjustments, catalytic group rearrangements, or changes in subunit assembly. Crystallographic structures were determined for several reconstructed ancestral proteins belonging to a GFP class frequently employed in superresolution microscopy. Their chain flexibility was analyzed using molecular dynamics and perturbation response scanning. The green-to-red photoconvertible phenotype appears to have arisen from a common green ancestor by migration of a knob-like anchoring region away from the active site diagonally across the β barrel fold. The allosterically coupled mutational sites provide active site conformational mobility via epistasis. We propose that light-induced chromophore twisting is enhanced in a reverse-protonated subpopulation, activating internal acid-base chemistry and backbone cleavage to enlarge the chromophore. Dynamics-driven hinge migration may represent a more general platform for the evolution of novel enzyme activities.
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U2 - 10.1016/j.str.2014.11.011
DO - 10.1016/j.str.2014.11.011
M3 - Article
C2 - 25565105
AN - SCOPUS:84920973895
VL - 23
SP - 34
EP - 43
JO - Structure with Folding & design
JF - Structure with Folding & design
SN - 0969-2126
IS - 1
ER -