Proteins are, among others, the macromolecules that perform all important tasks in organisms, such as catalysis of biochemical reactions, transport of nutrients, recognition, and transmission of signals. Thus, genes are the blueprints or library, and proteins are the machinery of life. Proteins are formed by joining amino acids by peptide bonds into a stretched chain.
Sequence determines structure determines function.
Thus, all information about the native structure of a protein is coded in the amino acid sequence, plus its native solution environment. In principle, the code could by deciphered from physico-chemical principles using, for example, molecular dynamics methods. In practice, however, such approaches are frustrated by two principle obstacles. Thus, the inaccuracy in experimentally determining the basic parameters, and the limited computing resources become fatal for predicting protein structure from first principles. The only successful structure prediction tools are knowledge-based, using a combination of statistical theory and empirical rules.