Purification and properties of DNA-dependent DNA-polymerases from Neurospora crassa.

AUTOR(ES)

Joester, W

RESUMO

Two DNA-dependent DNA-polymerases (E.C. 2.7.7.7) are partially purified from the high speed supernatant of mechanically disrupted hyphae of Neurospora crassa WT 74A. Some properties such as temperature and pH optimum and theoptimal concentrations for Mg2+, Zn2+, NH4+ and Na+ are very similar. On the other hand these enzymes show different properties on ion-exchange columns, are well distinguished by molecular weight (147 000 d and 110 000 d for A and B resp.) and the stimulation by K+ differs (K+ optimum for A: 5-70 mM and for B: 45 mM). Mn2+ and Zn2+ inhibit incorporation of deoxyribonucleoside monophosphates between 70 and 90%. Our best preparations so far have specific activities of 13 200 units/mg protein for A and 12 000 units/mg protein for B.

Documentos Relacionados

• Purification and Characterization of DNA-dependent RNA Polymerases from Cauliflower Nuclei 1
• RNA Polymerases of Maize. Purification and Molecular Structure of DNA-dependent RNA Polymerase II*
• DNA-Dependent DNA Polymerases I and II from Normal Human-Blood Lymphocytes
• Purification of vacuoles from Neurospora crassa.
• Properties of a DNA-dependent ATPase from rat mitochondria.