Magnetic Circular Dichroism Spectroscopy of Metalloproteins

  • Brian J. HalesEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1876)


Metals and metal clusters in proteins typically serve as important structural/functional motifs. Because of this reason, there is a wide range of techniques that specifically probe the structure and energy levels of metals in metalloproteins. One technique, magnetic circular dichroism (MCD) spectroscopy, is the focus of this chapter. MCD spectroscopy monitors the circular dichroism spectrum induced by a magnetic field and is an effective way of obtaining electronic and structural information of paramagnetic metal ions or clusters. The basic methodology of this technique is discussed along with examples of how MCD spectroscopy can be used to elucidate typical metal clusters in proteins. Special emphasis is placed on iron–sulfur (FeS) clusters.

Key words

MCD spectroscopy EPR spectroscopy Spin–orbit coupling Integer spin states Paramagnetism Zero-field splitting Magnetization curves 


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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of ChemistryLouisiana State UniversityBaton RougeUSA

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