Related Experiment Video
Updated: Oct 23, 2026

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Structural features of the protoporphyrin-apomyoglobin complex: a proton NMR spectroscopy study
1Department of Chemistry, Pennsylvania State University, University Park 16802.
Abstract:
The structural properties of the complex formed by apomyoglobin and protoporphyrin IX (des-iron myoglobin) were studied to probe the influence of iron-to-histidine coordination on the native myoglobin fold and the heme binding site geometry. Standard two-dimensional proton nuclear magnetic resonance spectroscopy methods were applied to identify porphyrin and protein signals. A pronounced spectral resemblance between carbonmonoxymyoglobin and des-iron myoglobin was noticed that could be exploited to assign a number of resonances by nuclear Overhauser spectroscopy. Protoporphyrin IX was determined to bind in the same orientation as the heme. Most residues in contact with the prosthetic group were found in the holomyoglobin conformation. Several tertiary structure features were also characterized near the protein termini. It was concluded that the protoporphyrin-apomyoglobin interactions are capable of organizing the binding site and the unfolded region of the apoprotein into the native holoprotein structure.
More Related Videos
10:03Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
14:55Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Related Concept Videos
Gene Families
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Globular and Fibrous Proteins
Globular proteins are also known as spheroproteins and typically are approximately round in shape. They contain a mix of amino acid types and contain differing sequences in their primary structures. Globular proteins have many different functions, such as enzymes, cellular messengers, and molecular transporters. These roles often require the proteins to be...
Proton (¹H) NMR: Chemical Shift
Absorption signals of all the protium nuclei in a...
¹H NMR: Complex Splitting
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
Interpreting ¹H NMR Signal Splitting: The (n + 1) Rule
NMR Spectroscopy Of Amines