GENETIC ALGORITHMS IN LOW RESOLUTION PROTEIN STRUCTURE DETERMINATION


E. Pantos, P. Chacon, F. Moran, J.F. Diaz, J.M. Andreu
CLRC, Daresbury Laboratory

A genetic algorithm for iterative fitting of SAXS data is described. A population of genes codifying a given mass distribution is randomly generated. From each genotype information the corresponding model structures can be processed by a SAXS simulation procedure and compared to experimental data. The reproductive fitness is used to generate the next population by mutation and two-point crossover recombination using an elitist strategy to enhances the GA performance. The algorithm described produces fast convergence to a fittest model mass distribution. This method affords a dramatic reduction of memory and processor time required by other SAXS fitting methods. The effectiveness of the procedure is demonstrated with synthetic objects, and by deriving a 16nm resolution model of a known protein structure from the corresponding computed SAXS profiles.

(posted 15-Oct-97 jw)