RESUMO
Microdochium nivale carbohydrate oxidase was produced by heterologous recombinant expression in Aspergillus oryzae, purified and crystallized. The enzyme crystallizes with varying crystal morphologies depending on the crystallization conditions. Several different crystal forms were obtained using the hanging-drop vapour-diffusion method, two of which were used for diffraction measurements. Hexagon-shaped crystals (form I) diffracted to 2.66 A resolution, with unit-cell parameters a = b = 55.7, c = 610.4 A and apparent space group P6(2)22. Analysis of the data quality showed almost perfect twinning of the crystals. Attempts to solve the structure by molecular replacement did not give satisfactory results. Recently, clusters of rod-shaped crystals (form II) were grown in a solution containing PEG MME 550. These crystals belonged to the monoclinic system C2, with unit-cell parameters a = 132.9, b = 56.6, c = 86.5 A, beta = 95.7 degrees . Data sets were collected to a resolution of 2.4 A. The structure was solved by the molecular-replacement method. Model refinement is currently in progress.
Assuntos
Desidrogenases de Carboidrato/química , Xylariales/enzimologia , Sequência de Aminoácidos , Aspergillus oryzae/genética , Desidrogenases de Carboidrato/genética , Desidrogenases de Carboidrato/isolamento & purificação , Desidrogenases de Carboidrato/metabolismo , Clonagem Molecular , Cristalização , Cristalografia por Raios X , Coleta de Dados , Galactose/metabolismo , Vetores Genéticos , Ponto Isoelétrico , Dados de Sequência Molecular , Peso Molecular , Homologia de Sequência de Aminoácidos , Estatística como Assunto , Especificidade por Substrato , Temperatura , Fatores de Tempo , Difração de Raios X , Xylariales/genética , Xilose/metabolismoRESUMO
The effective catalytic properties of enzymes have already promoted their introduction into several industrial products and processes. Recent developments in biotechnology, particularly in areas such as protein engineering and directed evolution, have provided important tools for the efficient development of new enzymes. This has resulted in the development of enzymes with improved properties for established technical applications and in the production of new enzymes tailor-made for entirely new areas of application where enzymes have not previously been used.