English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/23744
Compartir / Impacto:
Estadísticas
Add this article to your Mendeley library MendeleyBASE
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Título

Bis-(5'-guanosyl) tetraphosphatase in rat tissues

AutorCameselle, José C.; Costas, María J.; Günther Sillero, María A.; Sillero, Antonio
Fecha de publicación1-feb-1982
EditorBiochemical Society
CitaciónBiochemical Journal 201(2): 405-410 (1982)
ResumenThe occurrence and distribution of bis-(5'-guanosyl) tetraphosphatase activity towards dinucleoside tetraphosphates between the 27 000 g supernatant and sedimented fraction were studied in liver, kidney, brain, muscle and intestinal mucosa from rat. The p1p4-bis-(5'-guanosyl) tetraphosphate-hydrolysing activities found in total homogenates were 0.77, 1.44, 0.39, 0.36 and 2.14 units (mumol/min)/g respectively. The activities found in the 27000 g-sedimented fractions were 74, 49, 11, 4 and 96% of those present in the homogenates respectively. The properties of the soluble enzymes were investigated. All of them have low Km values for p1p4-bis-(5'-guanosyl) tetraphosphate (from 2 to 50 microM), are competitively inhibited by guanosine 5'-tetraphosphate with K1 values from 10 to 160 nM, have molecular weights of about 21 000, require Mg2+ or Mn2+ and are inhibited by Ca2+. These properties show that bis-(5'-guanosyl) tetraphosphatase (EC 3.6.1.17), an enzyme previously characterized in Artemia salina and rat liver [Warner & Finamore (1965) Biochemistry 4, 1568-1575; Vallejo, Sillero & Sillero (1974) Biochim, Biophys. Acta 358, 117-125; Lobatón, Vallejo, Sillero & Sillero (1975) Eur. J. Biochem. 50, 495-501], is present in all the rat tissues examined. The inhibition of the enzyme by Ca2+ could be related to the effect of p1p4-bis-(5'-adenosyl) tetraphosphate as a trigger of DNA synthesis [Grummt, Waltl, Jantzen, Hamprecht, Huebscher & Kuenzle (1979) Proc. Natl. Acad. Sci. U.S.A. 76, 6081-6085].
Descripción6 pages, 1 figure, 2 tables.-- Los autores pertenecen al antiguo Instituto de Enzimología del CSIC.
Versión del editorhttp://www.ncbi.nlm.nih.gov/pmc/articles/PMC1163657/
URIhttp://hdl.handle.net/10261/23744
ISSN0264-6021
Aparece en las colecciones: (IIBM) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
Bis 5' guanosyl.pdf916,52 kBAdobe PDFVista previa
Visualizar/Abrir
Mostrar el registro completo
 


NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.