Bac-to-Bac™ Baculovirus Expression System

The concentration of gentamicin might be too high. Try lowering the amount to 5 µg/mL and try adding more of the colony to the culture medium.

In the case of a blue colony, the E. coli has the bacmid and the plasmid in it, allowing the cells to survive the selection process. However, because the transposition has not occurred, the LacZ gene is not disrupted. For bulls-eye colonies, this indicates that the transposition took place when the colony was growing. Re-streaking for an isolated clone from the white portion of the mixed colony should yield some colonies where transposition occurred.

This is typically an indication of poor homologous recombination. Check the plasmid/linear DNA ratio you used. If there are some blue plaques, however, expand those viruses and check for their protein. In our experience, they are correct, even if they were in relatively low abundance.

Yes, cells are infected with wild-type virus individually and will develop polyhedra at different rates until all the cells in the flask are infected. The polyhedra in cells will form in approximately 3-4 days, differing in size and number until they reach their maximum capacity and burst the cell, releasing tiny particles of virus into the medium.

Normally, very small white dots show up about 5-7 days and 1 mm plaques show up around day 10. Plaques can vary in size from 1 mm to 4 mm.