Protein, molecular imaging

The European Molecular Biology Laboratory s (EMBL s) offers a well-equipped pro-teomics laboratory in its facilities at the Proteomics Visitor Facility (Heidelberg, Germany). The services in MB concern protein isolation, imaging, and robotics sample preparation, supported by some other analytical facilities. 

R. M. Caprioli, T.B. Farmer and J. Gile, Molecular imaging of biological samples localization of peptides and proteins using MALDI TOF MS, Anal. Chem., 69, 4751 4760 (1997). 

The protein A layer was incubated for 1 h to be cross-linked by glutaraldehyde, which was followed by transfer to a compartment containing ultrapure water for rinsing. The protein A molecular membrane was then transferred onto the surface of an HOPG plate by the horizontal method. The molecular imaging of the preparation was obtained by AFM in solution. 

The crude molecular image seen in the F0 map, which is obtained from the original indexed intensity data (IFobsI) and the first phase estimates (a calc), serves now as a model of the desired structure. A crude electron density function is devised to describe the unit-cell contents as well as they can be observed in the first map. Then the function is modified to make it more realistic in the light of known properties of proteins and water in crystals. This process is called, depending on the exact details of procedure, density modification, solvent leveling, or solvent flattening. 

In general, 2D correlations of any two distinct, non-collinear, anisotropic spin interactions provide molecular images, like PISA wheels in the PISEMA spectrum. For proteins, spectra obtained from suitable combinations... 

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