A new form of DNA polymerase 3 and a copolymerase replicate a long, single-stranded primer-template.
نویسندگان
چکیده
A new form of DNA polymerase III, termed Pol III star (Pol III(*)), has been purified to homogeneity from Escherichia coli. Pol III(*) is temperature sensitive when isolated from a thermo-sensitive dnaE mutant, as had been described for Pol III. Pol III(*) and Pol III are separable by gel filtration. Pol III(*) utilizes a duplex template containing short gaps with the same catalytic properties as Pol III. However, Pol III(*) is able to replicate long, singlestranded templates such as homopolymer chains and viral circles of M13 and varphiX174 if provided with the following: spermidine, a primer fragment, and a new protein, termed copolymerase III(*) (Copol III(*)). The latter, purified to homogeneity, has no known independent enzymatic activity and supports synthesis by Pol III(*) but not by Pol I, Pol II, or Pol III.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 70 6 شماره
صفحات -
تاریخ انتشار 1973