Protein Databases
Protein databases store information about protein structures, sequences, and functions. They come from experimental methods or computational predictions.
PDB
Definition
What is PDB? PDB (Protein Data Bank) is the main global database that stores 3D structures of proteins, DNA, RNA, and their complexes.
How experimental structure data is obtained? (3 methods)
- X-ray Crystallography(88%): uses crystals + X-ray diffraction to map atomic positions.
- NMR Spectroscopy(10%): uses magnetic fields to determine structures in solution.
- Cryo-Electron Microscopy (Cryo-EM)(1%)
What is a Ligand?: A ligand is any small molecule, ion, or cofactor that binds to the protein in the structure, often to perform a specific biological function. Example: iron in hemoglobin
What is Resolution (Å)? Resolution (in Ångström) measures the level of detail; smaller value = sharper, more accurate structure.