Assignment of protein backbone resonances using connectivity, torsion angles and ¹³C[alpha] chemical shifts

by (Laura Christine), 1964- Morris

A computer program is presented that will return the most probable sequence location for a short connected set of residues in a protein given just 13C? chemical shifts (?C?) and data restricting the phi and psi backbone angles. Data taken from both the BioMagResBank and the Protein Data Bank were used to create a probability density function (PDF) using a multivariate normal distribution in ?C?, ?, and ? space for each amino acid. Extracting and combining probabilities for particular amino acids in a short proposed sequence yields a score indicative of the correctness of the proposed assignment. The program is illustrated using several proteins for which structure and 13C? chemical shift data are available.