RCAS, AS and BST, NTU

PI: Kuo Kan Liang 梁國淦

Annual ReportDiCK / SLaBS

RCAS, Academia Sinica

RCAS, AS and BST, NTU

Theme of Researches

Chemical reactions and transport processes in biological systems– Special emphases: Membrane protein ion channels

Methodology:– Spectroscopic methods– Electrochemistry methods– Both include theory and experiments

RCAS, AS and BST, NTU

Methodology:Spectroscopic Methods

Eternal goal: Spectroscopic observation of the kinetics with as little labeling as possible

IR spectroscopy;– Mid-IR range observation of amide-I peaks– Ultrafast multiphoton coherent spectroscopy such

as 2D-IR– Time-resolved FT-IR

Fluorescence spectroscopy:– Natural amino acids: Tryptophan, tyrosine

RCAS, AS and BST, NTU

Methodology:Spectroscopic Methods

Protein backbone modes couplings can be observed as vibration coherence as well as mode anharmonicity

Past achievements– Theory of anharmonic effect on absorption lineshape– Theory of effect of near-by vibronic level on the 3-

pulse photon echo signal of a vibration mode– Theory of anharmonic and mode-mode coupling

effect on the 3-pulse photon echo signal of a vibration mode.

RCAS, AS and BST, NTU

Publications:Spectroscopic Methods

Chu, Z.*; Liang, K. K.*; Hayashi, M.; Lin, S. H., “Theoretical treatment of anharmonic effect on molecular absorption, fluorescence spectra, and electron transfer”, Chem. Phys. 2009, 358, 137.

RCAS, AS and BST, NTU

Publications:Spectroscopic Methods

Villaeys, A. A.*; Dappe, Y.; Liang, K. K.; Lin, S. H., “Influence of neighboring levels in three-pulse photon-echo processes”, Phys. Rev. A 2009, 79, 053418. (Virtual Journal of Ultrafast Science 2009, Vol. 8, Issue 6)

RCAS, AS and BST, NTU

Publications:Spectroscopic Methods

Liang, K. K.*; Villaeys, A. A., “Anharmonicity and mode-mode coupling effects analyzed by 4WM photon-echo spectroscopy”, Phys. Rev. A 2010 (Accepted with minor corrections).

Methodology:Electrochemistry Methods

Impedance spectroscopy (transfer function) of ion channels

Modified electrophysiology (patch-clamp) experiments– Patch-clamp impedance spectroscopy– Patch-Clamp fluorometry (Electrophysiology +

Spectroscopy)– Time-resolved experiments: synchronization method

RCAS, AS and BST, NTU

Publication:Electrophysiology Methods

Chang, H.-K.; Martin, L. J.; Liang, K. K.; Shieh, R.-C.*, “K+ binding in G-loop and water cavity facilitates Ba2+ movement in the Kir2.1 Channel”, Biochim. Biophys. Acta 2009, 1788, 500.

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short longMembrane voltage

Hill plot:Hill coefficient ~ 2.5Indicating that cooperative binding is not the sole story

RCAS, AS and BST, NTU

Further Developments:Short term

Theory of kinetics of cooperative systems * Stochastic model of ion transport in channels * Molecular dynamics simulations and analysis of

hydrated cations transport in bulk and in artificial channels

Patch-clamp fluorometry of unlabeled Kir 2.1/ 2.2 channels

RCAS, AS and BST, NTU

Further Developments:Mid-term

Impedance of ion channels– Theoretical method: Chemical kinetics simulation of

the ion transport process in ion channels– Experimental method: AC patch-clamp

Advanced materials for CO2 separation– Theory of CO2 or CO3

2– transport in pores such as in polymer-metal framework (PMF)

– Model system construction for cell-free CO2 reduction using enzymes

RCAS, AS and BST, NTU

Further Developments:Long-term

Thermodynamics and kinetics of single- / few- biological-macromolecule events– Theory of reactive transport in pores / channels– Thermodynamics and kinetics of binding in channels– Thermodynamics systems with electrostatic works

Electrochemical and structural kinetics of cells– Synchronous observations of reactions, transport

processes, and structural changes on membrane– Engineering of cellular or cell-free molecular

factories