the tertiary structure of soluble globular proteins is more advanced than that of membrane proteins because the former are easier to study with available technology. X-ray crystallography X-ray crystallography is the most common tool used to determine protein structure. It provides high resolution of the structure but it does not give information about protein's conformational flexibility. NMR Protein NMR gives comparatively lower resolution of protein structure. It is limited to smaller proteins. However, it can provide information about conformational changes of a protein in solution. Cryogenic electron microscopy Cryogenic electron microscopy (cryo-EM) can give information about both a protein's tertiary and quaternary structure. It is particularly well-suited to large proteins and symmetrical complexes of protein subunits. Dual polarisation interferometry Dual polarisation interferometry provides complementary information about surface captured proteins. It assists in determining structure and conformation changes over time. Projects Prediction algorithm The Folding@home project at Stanford University is a distributed computing research effort which uses approximately 5 petaFLOPS (≈10 x86 petaFLOPS) of available computing. It aims to find an algorithm which will consistently predict protein tertiary and quaternary structures given the protein's amino acid sequence and its cellular conditions. A list of software for protein tertiary structure prediction can be found at List of protein structure prediction software. Protein aggregation diseases Protein aggregation diseases such as Alzheimer's disease and Huntington's disease and prion diseases such as bovine spongiform encephalopathy can be better understood by constructing (and reconstructing) disease models. This is done by causing the disease in laboratory animals, for example, by administering a toxin, such as MPTP to cause Parkinson's disease, or through genetic manipulation. Protein structure prediction is a new way to create disease models, which may avoid the use of animals. Protein Tertiary Structure Retrieval Project (CoMOGrad) Matching patterns in tertiary structure of a given protein to huge number of known protein tertiary structures and retrieve most similar ones in ranked order is in the heart of many research areas like function prediction of novel proteins, study of evolution, disease diagnosis, drug discovery, antibody design etc. The CoMOGrad project at BUET is a research effort to device an extremely fast and much precise method for protein tertiary structure retrieval and develop online tool based on research outcome. See also Folding (chemistry) I-TASSER Nucleic acid tertiary structure Protein contact map Proteopedia Structural biology Structural motif Protein tandem repeats References External links Protein Data Bank Display, analyse and