Characterization of DNA polymerases in mature sperm of the sea urchin.

In the extract of mature sperm of the sea urchin, Hemicentrotus pulcherrimus, two species of DNA polymerase (deoxynucleosidetriphosphate:DNA deoxynucleotidyltransferase, EC 2.7.7.7.) activity were detected. One of them was eluted from a hydroxyapatite column at 0.08 M phosphate buffer and was insensitive to both N-ethylmaleimide and aphidicolin. The sedimentation coefficient was 3.3 S and the isoelectric point was pH 8.6. This activity corresponds to the DNA polymerase-beta activity. The other was eluted from the hydroxyapatite column at 0.14 M phosphate buffer and was inhibited by N-ethylmaleimide but not by aphidicolin. The sedimentation coefficient was 3.3 S and 6.0 S and the isoelectric point was pH 4.8. The template primer preference of this enzyme was coincident with DNA polymerase-gamma. The DNA polymerase-alpha activity was not detected in the extract of mature sperm.