title: Predicting resistance mutations using protein design algorithms.
abstract: Drug resistance resulting from mutations to the target is an unfortunate common phenomenon that limits the lifetime of many of the most successful drugs. In contrast to the investigation of mutations after clinical exposure, it would be powerful to be able to incorporate strategies early in the development process to predict and overcome the effects of possible resistance mutations. Here we present a unique prospective application of an ensemble-based protein design algorithm, K*, to predict potential resistance mutations in dihydrofolate reductase from Staphylococcus aureus using positive design to maintain catalytic function and negative design to interfere with binding of a lead inhibitor. Enzyme inhibition assays show that three of the four highly-ranked predicted mutants are active yet display lower affinity (18-, 9-, and 13-fold) for the inhibitor. A crystal structure of the top-ranked mutant enzyme validates the predicted conformations of the mutated residues and the structural basis of the loss of potency. The use of protein design algorithms to predict resistance mutations could be incorporated in a lead design strategy against any target that is susceptible to mutational resistance.
authors.affiliation: Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269, USA.
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Frey
authors.forename: Ivelin
authors.initials: I
authors.lastname: Georgiev
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Donald
authors.forename: Amy C
authors.initials: AC
authors.lastname: Anderson
mesh_terms: D000465:Algorithms; D055162:Biocatalysis; D001699:Biometry; D018360:Crystallography, X-Ray; D024881:Drug Resistance, Bacterial; D005493:Folic Acid Antagonists / Q000737:chemistry* / Q000494:pharmacology; D008958:Models, Molecular; D009154:Mutation; D017434:Protein Structure, Tertiary; D013211:Staphylococcus aureus / Q000201:enzymology* / Q000235:genetics; D013329:Structure-Activity Relationship; D013762:Tetrahydrofolate Dehydrogenase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D005493:Folic Acid Antagonists; D013762:Tetrahydrofolate Dehydrogenase