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Physical Sciences and Mathematics Commons

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Mark J. Waner

Selected Works

1998

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Charge Density Wave Caused By Reducing Thse3 By One Electron. Superstructure And Short-Range Order In Ath2se6 (A = K, Rb) Studied By X-Ray Diffraction, Electron Diffraction, And Diffuse Scattering, Kyoung-Shin Choi, Rhonda Patschke, Simon Billinge, Mark Waner, Marcos Dantus, Mercouri Kanatzidis Oct 1998

Charge Density Wave Caused By Reducing Thse3 By One Electron. Superstructure And Short-Range Order In Ath2se6 (A = K, Rb) Studied By X-Ray Diffraction, Electron Diffraction, And Diffuse Scattering, Kyoung-Shin Choi, Rhonda Patschke, Simon Billinge, Mark Waner, Marcos Dantus, Mercouri Kanatzidis

Mark J. Waner

Charge Density Wave Caused by Reducing ThSe3 by One Electron. Superstructure and Short-Range Order in ATh2Se6 (A = K, Rb) Studied by X-ray Diffraction, Electron Diffraction, and Diffuse Scattering


Imaging The Molecular Dimensions And Oligomerization Of Proteins At Liquid/Solid Interfaces, Mark Waner, Martha Gilchrist, Melvin Schindler, Marcos Dantus Feb 1998

Imaging The Molecular Dimensions And Oligomerization Of Proteins At Liquid/Solid Interfaces, Mark Waner, Martha Gilchrist, Melvin Schindler, Marcos Dantus

Mark J. Waner

Individual Concanavalin A (ConA) molecules have been imaged at the liquid/solid interface with an atomic force microscope (AFM). Three-dimensional sizing with very high resolution (<5 Å) has been obtained by a novel approach based on height distributions, which avoids the tip convolution effects which normally affect scanning probe microscopy techniques. Each height measurement correlates to a particular molecular orientation on the surface. A large number of such measurements provide a statistical ensemble of orientations. The complete height distribution reflects the three-dimensional size of the protein sample and hence its tertiary and quaternary structure. A surface adsorption and orientation model, based on a minimization of surface adsorption energy, is proposed. This model is in good agreement with the observed height distribution of Con A molecules at the liquid/solid interface. Analysis of Con A and succinylated Con A molecules on mica demonstrates that Con A dimers are the prevalent species at the liquid/solid interface. This is in contrast to the tetrameric organization of Con A normally observed in solution. The new possibilities opened by height distribution analysis on the physical characterization of biomolecules at interfaces are also discussed.