An Overview of Protein Structure Research Techniques

The study of protein structure plays a very crucial role in many kinds of biological researches. However, it is really tedious and complex to analyze protein structure. There are some methods for studying protein structure.

Those techniques are including but not limited to:

• X-ray single crystal diffraction analysis technology
• a href="http://www.creative-biostructure.com/nmr-services_28.htm">Nuclear Magnetic Resonance

Technology

• Protein two-dimensional crystallization and three-dimensional reconstruction techniques
• Scanning Probe Microscopy

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X-ray single crystal diffraction analysis technology

Thoery: when a beam of x-rays impinges on the crystal, x-rays cause diffraction in the crystal. The diffraction patterns produced by the crystals reflect the atomic distribution inside the crystal. Using the photographic method to collect diffraction rays, which can make the film photosensitive and leave the corresponding diffraction pattern.

Main steps for X-ray crystallography:

• Crystal culture
• Data collection and processing
• Determination of phase
• Calculation and explanation of electron density map
• Structural model correction

Nuclear Magnetic Resonance Technology

Theory: under the action of an external magnetic field, the non-zero nuclear spins Zeeman splitting, absorbing resonance of a particular frequency of radio frequency radiation.

The conditions of nuclear magnetic resonance:

• The frequency of the fixed electromagnetic waves gradually changes the applied magnetic field.
• Fixed magnetic field changes the frequency of electromagnetic waves.

NMR has the high respectively rate and can be processed in the solutions.

Scanning Probe Microscopy (SPM)

The family of Scanning Probe Microscopy has STM and AFM. Their work theories are tunneling current and interaction force between the tip and the sample separately.

SPM has the ability of a high spatial resolution, real-time imaging and an atomic image under certain conditions. Because protein molecules must rely on a certain media environment to maintain its biological and chemical activity, protein imaging is usually in the buffer.

In addition to the several methods mentioned above, the study of protein structure field still has a lot of magic techniques, such as molecular simulation technology, crosslinked mass spectrometry, spectral technique of conformation of protein solution and so on.

Structural biology, especially protein structure determination is full of magic.