Atomic Force Microscopy of Chromatin
نویسندگان
چکیده
Atomic force microscopy or scanning tunneling microscopy (AFM/STM) is a powerful single molecule tool for the visualization of biological materials at sub-nanometer resolution. AFM is versatile because it can directly measure physical properties due to its sensitivity at picoNewton force scales, thus enabling dissection of molecular forces. STM/AFM has been considered revolutionary since its discovery 32 years ago, and a mere 7 years after its invention, Binnig and Rohrer were awarded the Nobel Prize in Physics, along with Ruska, inventor of the first electron microscope. In subsequent years, AFM has evolved fast, with the range of applications for STM/AFM expanding to encompass all physical sciences. Despite it’s popularity in physics, engineering, material and chemistry sciences, it has remained a less prominent tool for biologists, who are much more familiar with techniques like electron microscopy (EM), X-ray crystallography or nuclear magnetic resonance (NMR). The relatively low cost of the microscope, the ease of sample preparation, and the lack of any requirement for staining, freezing, excessive denaturation or preservation, should make AFM an ideal tool for laboratories interested in imaging and manipulating biological samples down to macromolecules at the nanoscale. In this chapter, we will discuss how AFM can be an effective high-resolution technique for structural and molecular interaction studies in biology.
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