title: DNA polymerase-primase from embryos of Drosophila melanogaster. The DNA polymerase subunit.
abstract: The DNA polymerase-primase from Drosophila melanogaster has been separated into its constituent polymerase and primase subunits by sedimentation in glycerol gradients containing 50% ethylene glycol. Both activities have been obtained in good yield. The properties of the 182-kDa polymerase subunit are similar to those of the intact four-subunit enzyme. However, there are three significant differences. (i) The polymerase activity of the 182-kDa subunit shows an increased thermolability; (ii) the pause sites during replication of singly primed, single-stranded circular DNA by the 182-kDa subunit are altered; and (iii) unlike the intact enzyme, the 182-kDa subunit is highly processive in the presence of the single-stranded DNA-binding protein of Escherichia coli.
mesh_terms: D000818:Animals; D019915:DNA Primase; D004259:DNA-Directed DNA Polymerase / Q000302:isolation & purification* / Q000378:metabolism; D004331:Drosophila melanogaster / Q000196:embryology / Q000201:enzymology*; D004625:Embryo, Nonmammalian / Q000201:enzymology; D007700:Kinetics; D046911:Macromolecular Substances; D008970:Molecular Weight; D012316:RNA Nucleotidyltransferases / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D046911:Macromolecular Substances; D019915:DNA Primase; D012316:RNA Nucleotidyltransferases; D004259:DNA-Directed DNA Polymerase