The importance of dynamic effects on the enzyme activity: X-ray structure and molecular dynamics of onconase mutants(670 views) Merlino A, Mazzarella L, Carannante A, Di Fiore A, Di Donato A, Notomista E, Sica F
Keywords: Computer Simulation, Crystal Structure, Molecular Dynamics, Toxicity, Tumors, X Ray Analysis, Catalytic Activity, Mutants, Onconase, Enzymes, Cysteine, Disulfide, Mutant Protein, Ranpirnase, Ribonuclease A, Recombinant Protein, Article, Cancer, Cancer Chemotherapy, Catalysis, Disulfide Bond, Drug Structure, Enzyme Activity, Enzyme Stability, Frog, Nephrotoxicity, Priority Journal, Structure Analysis, Thermostability, Animal, Chemical Structure, Chemistry, Enzyme Activation, Genetics, Metabolism, Methodology, Mutation, Physiology, X Ray Crystallography, Amphibia, Rana Pipiens, X-Ray, Models,
Affiliations: *** IBB - CNR ***
Dipartimento di Chimica, Università degli Studi di Napoli Federico II, Via Cynthia, 80126 Napoli, Italy
Centro Regionale di Competenza-Bioteknet, Complesso Ristrutturato S. Andrea Delle Dame, Via L. De Crecchio, 7, 80138 Napoli, Italy
Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale Delle Ricerche, Via Mezzocannone 6, 80134 Napoli, Italy
Dipartimento di Biologia Strutturale e Funzionale, Università Federico II, Via Cynthia, 80126 Napoli, Italy
References: Not available.
The importance of dynamic effects on the enzyme activity: X-ray structure and molecular dynamics of onconase mutants
Onconase (ONC), a member of the RNase A superfamily extracted from oocytes of Rana pipiens, is an effective cancer killer. It is currently used in treatment of various forms of cancer. ONC antitumor properties depend on its ribonucleolytic activity that is low in comparison with other members of the superfamily. The most damaging side effect from Onconase treatment is renal toxicity, which seems to be caused by the unusual stability of the enzyme. Therefore, mutants with reduced thermal stability and/or increased catalytic activity may have significant implications for human cancer chemotherapy. In this context, we have determined the crystal structures of two Onconase mutants (M23L-ONC and C87S, desl03-104-ONC) and performed molecular dynamic simulations of ONC and C87S, desl03-104-ONC with the aim of explaining on structural grounds the modifications of the activity and thermal stability of the mutants. The results also provide the molecular bases to explain the lower catalytic activity of Onconase compared with RNase A and the unusually high thermal stability of the amphibian enzyme. 2005 by The American Society for Biochemistry and Molecular Biology, Inc
The importance of dynamic effects on the enzyme activity: X-ray structure and molecular dynamics of onconase mutants