flashBAC ULTRA (cat# 100304/100300/100301/100302) is the latest development in the series of flashBAC™ vectors. In addition to chiA (chitinase) and v-cath (cathepsin), three more virus genes (p10, p74 and p26) have been excised from the flashBAC ULTRA genome. The deletion of chiA has improved the efficacy of the secretory pathway whilst the absence of v-cath reduces the chance of the recombinant protein being degraded. Deletion of p10 increases polyhedrin promoter activity providing greater nuclear and cellular stability, ensuring a longer timeframe for protein expression and removes a major competitor for limiting cellular resources. Removing p74 further increases the biosafety profile of recombinant baculoviruses in the environment, making them unable to traverse the insect gut wall. Along with p26, the absence of these genes removes an unnecessary genetic burden from the recombinant virus genome, providing a more efficient baculovirus expression vector. This has allowed further improvements in recombinant protein yield and quality to be delivered, making flashBAC ULTRA the best choice for the most difficult to express proteins.
Using the flashBAC™ system is easier and quicker than other baculovirus expression systems because there is no need to separate recombinant virus from parental virus by plaque-purification or any other means; only recombinant virus is produced after the co-transfection. Because the production of recombinant virus has been reduced to a single step procedure in insect cells, it is amenable to high throughput and automated production systems. However, it is also of benefit to the small research group requiring a low cost solution to producing one or a few recombinant baculoviruses prepared in individual dishes of cells.