Dr. Mohamed Chami

Biozentrum
University of Basel
at the Department for Biosystems Science and Engineering (D-BSSE)
Mattenstrasse 26
CH - 4058 Basel
WRO-1058, Room P 36 Phone: +41 61 387 32 24
Email: mohamed.chami-at-unibas.ch
Curriculum Vitae

BioEM Lab

The Contribution of Electron Microscopy to the Structural Biology

We offer electron microscopy (EM) structural investigations in the field of Biology. Our methods include cellular and molecular EM as well as reconstructions of cells, tissue sections and proteins.

Electron micrograph of viruses and nanobacteria living in the waste water. The scale bar is 0.2 micron.

The last few years have seen substantial advances in the use of EM techniques in the field of life sciences, through the introduction of a more accurate imaging system, microscopes equipped for high resolution and reliable data analysis procedures. This combination has allowed structural elements of biological samples to be determined in unprecedented detail. We apply various technical approaches to visualize the ultrastructural details of cells and determine the 3D structure of bio-macromolecules.

Single particle analysis: 

Used to determine the high-resolution three-dimensional (3D) structure of isolated frozen protein complexes using state of art of electron microscopes and electron detectors.

Thin sectioning: 

Allows the visualization of the ultrastructure of tissues and cells. Thin sections of samples are made at room temperature (classical method) or at low temperature (CEMOVIS) and are imaged in two dimensions (2D; projections) or 3D (tomography) by TEM.

Tomography and Sub-volume averaging: 

Used to visualize cellular samples in 3D. Images are recorded with the sample in different orientations and computationally integrated to give a 3D model of the imaged cell. Cryo conditions keep the sample in a close-to-native state, so that high-resolution structural information of the sample is preserved. Sub-tomogram averaging can be used to determine the 3D structure of proteins in their cellular environment.

Our services.

EM projects require the successful completion of three interlaced tasks: sample preparation, data acquisition, and image processing. The nature of the sample, the targeted resolution and the scope of the biological question determine the specific requirements in each of these areas.

Our goal is to define the best-suited workflow for each project, providing training, technical support and access to our infrastructure. We also provide consulting services to help our users setup and operate the required data analysis programs on the computing resources.

For further details please visit our website hosted by C-CINA:
https://c-cina.unibas.ch/bioem/