RESUMEN

Deoxynucleoside monophosphate kinase (dNMP kinase) of bacteriophage T5 (EC 2.7.4.13) was purified to apparent homogeneity from phage-infected Escherichia coli cells. Electrophoresis in sodium dodecyl sulfate-polyacrylamide gel showed that the enzyme has a molecular mass of about 29 kDa. The molecular mass of dNMP kinase estimated by analytical equilibrium ultracentrifugation turned out to be 29.14 +/- 3.03 kDa. These data suggest that the enzyme exists in solution as a monomer. The isoelectric point of dNMP kinase was found to be 4.2. The N-terminal amino acid sequence, comprising 21 amino acids, was determined to be VLVGLHGEAGSGKDGVAKLII. A comparison of this amino acid sequence and those of known enzymes with a similar function suggests the presence of a nucleotide-binding site in the sequenced region.

Asunto(s)

Bacteriófagos/enzimología , Fosfotransferasas (Aceptor del Grupo Fosfato)/química , Fosfotransferasas (Aceptor del Grupo Fosfato)/aislamiento & purificación , Secuencia de Aminoácidos , Sulfato de Amonio/farmacología , Resinas de Intercambio Aniónico/farmacología , Cromatografía por Intercambio Iónico , Desoxirribonucleótidos/metabolismo , Electroforesis en Gel de Poliacrilamida , Escherichia coli/enzimología , Concentración de Iones de Hidrógeno , Modelos Químicos , Datos de Secuencia Molecular , Estructura Terciaria de Proteína , Resinas Sintéticas , Programas Informáticos , Factores de Tiempo , Ultracentrifugación