00599nas a2200193 4500008004500000020001400045245009200059210006900151260000800220300001400228490000800242653001500250100001500265700002000280700001700300700001900317700002000336856004900356 2017 Engldsh a0006-349500aEscaping the Water Cage: Protein Intramolecular Vibrations and the Dynamical Transition0 aEscaping the Water Cage Protein Intramolecular Vibrations and th cFeb a318A-318A0 v11210aBiophysics1 aXu, M., Y.1 aNiessen, K., A.1 aDeng, Y., T.1 aMichki, N., S.1 aMarkelz, A., G. uhttps://markelz.physics.buffalo.edu/node/25600601nas a2200193 4500008004500000020001400045245009300059210006900152260000800221300001400229490000800243653001500251100001700266700001500283700001600298700002400314700002000338856004900358 2017 Engldsh a0006-349500aOrange Carotenoid Protein Picosecond Dynamics Changes with Photo and Chemical Activation0 aOrange Carotenoid Protein Picosecond Dynamics Changes with Photo cFeb a441A-441A0 v11210aBiophysics1 aDeng, Y., T.1 aXu, M., Y.1 aLiu, H., J.1 aBlankenship, R., E.1 aMarkelz, A., G. uhttps://markelz.physics.buffalo.edu/node/25001585nas a2200181 4500008004500000020002200045245010500067210006900172260001900241520099700260100001501257700001601272700001501288700001701303700001401320700002001334856004901354 2016 Engldsh a978-1-4673-8485-800aAnisotropic Absorption Measurements Reveal Protein Dynamical Transition in Intramolecular Vibrations0 aAnisotropic Absorption Measurements Reveal Protein Dynamical Tra aNew YorkbIeee3 a
Modeling has predicted that intramolecular structural vibrations enables proteins to access functionally important structural change. We show that the vibrational density of states and the isotropic absorption in the terahertz range are only weakly dependent on the protein functional state for several bench marking proteins. At the same time the direction of motions changes dramatically with functional state and with a resulting impact on the anisotropic absorption. Our anisotropic THz microscopy (ATM) measurements confirm this sensitivity. Here we apply the technique to the question of whether the protein dynamical transition (DT) is important to protein function. We find a strong anisotropic resonance at 70 cm(-1) rapidly increases in strength at temperatures above the DT. As these intramolecular vibrations enable protein structure to change conformation, the results suggest function will cease below DT for those proteins that require large scale conformational change.
1 aXu, M., Y.1 aNiessen, K.1 aMichki, N.1 aDeng, Y., T.1 aSnell, E.1 aMarkelz, A., G. uhttps://markelz.physics.buffalo.edu/node/24601399nas a2200169 4500008004500000020002200045245007600067210006900143260001900212520086600231653001301097100001501110700001901125700001601144700002001160856004901180 2014 Engldsh a978-1-4799-3877-300aProbing the Stability of Fluorescent Proteins by Terahertz Spectroscopy0 aProbing the Stability of Fluorescent Proteins by Terahertz Spect aNew YorkbIeee3 aThe higher transmission through tissues of long wavelength light motivates the development of fluorescent proteins with excitation shifted to the red. However red fluorescent proteins (RFPs) are more susceptible to photobleaching than their shorter wavelength counterparts. In particular RFPs are more susceptible to photobleaching [1]. A possible reason for this is a decrease in the structural stability of the beta barrel. Measurements of structural stability include atomic root mean squared displacement <x(2)> measured by the X-ray B-factor and neutron quasi elastic scattering. To date, X-ray measurements of RFP's do not indicate a structural stability change and systematic scattering studies have not been performed. Using THz dielectric response we examine if the picosecond structural flexibility decreases with increasing FP stability.
10adynamics1 aXu, M., Y.1 aGeorge, D., K.1 aJimenez, R.1 aMarkelz, A., G. uhttps://markelz.physics.buffalo.edu/node/245