HomeApplicationsProtein BiologyProtein Structural Analysis

Protein Structural Analysis

A 3D illustration of a complex protein structure with intertwined ribbons in various colors representing the folding of amino acid chains.

The function of a protein is directly dependent on its structure, its interactions with other proteins, and its location within cells, tissues, and organs. The structure and function of proteins is studied on a large scale in proteomics, which enables the identification of protein biomarkers associated with specific disease states and provides potential targets for therapeutic treatment. The understanding of protein structure and mapping of protein location, expression levels, and interactions yield valuable information that can used to infer protein function. 

Protein Structure
Protein Structure Determination
Protein Mapping

Related Technical Articles

  • Amino acid reference chart contains the twenty amino acids found in eukaryotes, grouped according to their side chains and charge. Discover our full product line of amino acids, including Alanine, Isoleucine, Leucine, Valine, Phenylalanine, Tryptophan, Tyrosine, Aspargine, Cysteine, Glutamine, Methionine, Serine, Threonine, Aspartic acid, Glutamic acid, Arginine, Histidine, Lysine, Glycine and Proline. Learn more today.
  • The human protein atlas has an aim of mapping all human proteins within cells, tissues and organs and providing open-access information to advance understanding of human biology and disease.
  • Information on Isoelectric Focusing including what it is and how it is used. In order to ensure the high performance of analysis, isoelectric point (pI) standards are needed.
  • We presents an informational article concerning biomolecular NMR and the use of Isotope Labeling Methods for Protein Dynamics Studies.
  • Glycosylphosphatidylinisotol (GPI) anchored proteins are membrane bound proteins found throughout the animal kingdom. GPI anchored proteins are linked at their carboxyterminus through a phosphodiester linkage of phosphoethanolamine to a trimannosyl-non-acetylated glucosamine (Man3-GlcN) core.
  • Glycan Sequencing Using Exoglycosidases
  • Sigma-Aldrich presents a Biofiles on Detect, Visualize and Quantify Single Post-Translational Modifications
  • See All (9)

Related Protocols

  • This page covers the principles and methods of chromatofocusing, a chromatography technique that separates proteins according to differences in their isoelectric point (pI).
  • Protein Structural Analysis
  • This protocol describes a method for chemical cross-linking of proteins using formaldehyde. With the exception of zero-length cross-linkers, formaldehyde has the shortest cross-linking span (~2-3 Å) of any cross-linking reagent, thus making it an ideal tool for detecting specific protein-protein interactions with great confidence.
  • See All (2)

Find More Articles and Protocols

Protein structure

Protein structure is determined by the sequence of amino acids that compose the protein and how the protein folds into more complex shapes.

  • Primary structure is defined by the amino acid sequence of the protein.
  • Secondary structure is defined by local interactions of stretches of the polypeptide chain, which can form α-helices and β-sheets through hydrogen bonding interactions.
  • Tertiary structure defines the overall three-dimensional structure of the protein.
  • Quaternary structure defines how multiple protein subunits interact to form larger complexes.

Protein Structure Determination

The determination of three-dimensional protein structures at atomic resolution is useful in the elucidation of protein function, structure-based drug design, and molecular docking.

  • NMR: Nuclear magnetic resonance (NMR) spectroscopy is used to obtain information about the structure and dynamics of proteins. In NMR, the spatial location of atoms is determined by their chemical shifts. For protein NMR, proteins are typically labeled with stable isotopes (15N, 13C, 2H) to enhance sensitivity and facilitate structural deconvolution. Isotopic labels are typically introduced by supplying isotopically labeled nutrients in the growth medium during protein expression.
  • X-ray crystallography: Protein X-ray crystallography can be used to obtain the three-dimensional structure of proteins through X-ray diffraction of crystallized proteins. Crystals are grown by seeding highly concentrated protein in solutions that promote precipitation, with ordered protein crystals forming under suitable conditions. X-rays are aimed at the protein crystal, which scatters the X-rays onto an electronic detector or film. The crystals are rotated to capture diffraction in three dimensions, enabling calculation of the position of each atom in the crystallized molecule by Fourier Transform.

Protein Mapping

Mapping of the location and expression level of proteins in specific cells, tissues, and organs aids in the functional study of the proteome. Spatial distribution of proteins is key to protein function, with improper localization or expression triggering various disease states. Mapping projects such as the Human Protein Atlas provide a proteomic resource for biomarker discovery and aid in the understanding of disease pathology. Mapping of the interactome helps define the molecular interactions that occur on a cellular level, assisting in the understanding of protein function and providing valuable potential drug targets for disease.

Related Product Resources

  • Bulletin: ISOGRO Media

    This technical bulletin is from ISOGRO Media, providing information on stable isotope enrichment of proteins for NMR spectroscopy.

Sign In To Continue

To continue reading please sign in or create an account.

Don't Have An Account?