Detection and isolation of a new DNA polymerase from human breast tumor cell line HBT-3 by (dT)12-18-cellulose chromatography.

Column chromatography on (dT)(12-18)-cellulose was used to detect and isolate a novel DNA polymerase activity from human breast tumor cell line HBT-3. The new enzyme is similar to those of mammalian RNA tumor viruses in its molecular size, preference for poly(A).(dT)(12-18) as compared to either poly(dA).(dT)(12-18) or poly(A).poly(dT), and ability to copy poly(C).(dG)(12-18). A similar DNA polymerase activity, defined by its binding to (dT)(12-18)-cellulose, is not detectable in several other cell lines of human tumors.