Ramachandran-Plot

A Ramachandran plot ( Ramachandran and Chart ) is a diagram illustrating the statistical distribution of combinations of two dihedral angles ( φ and ψ ) of a particular protein backbones. It is named after the Indian scientist GN Ramachandran.

Mathematically, the Ramachandran plot is thus a representation of a function.

Ramachandran plot are characteristic for respective specific types of protein molecules. One can estimate the molecular basis of a Ramachandran plot and the frequency of α -helices, β -sheets and other protein secondary structures.

The Ramachandran plot is an important module in computer programs that automatically selects the quality of the structure determinations ( crystal structure analysis, nuclear magnetic resonance spectroscopy, etc.) check with proteins, for example in WHATIF, PROCHECK or USF.