Imperfect Crystal – Inclusion Body

Protein Crystals. Image courtesy of NASA.

Formation of inclusion bodies is one of the most common complications in heterologous protein expression (1). Despite this complication, the E. coli expression system is still highly used for eukaryote protein expression. Is this practice based on knowledge or historic consequence? Continue reading

How to Use the Flexi® Vectors (Part 2 of 2)

pFN24K HaloTag® CMVd3 Flexi® VectorIn previous entries, I discussed the naming convention for the many Flexi® Vectors available from Promega before addressing how to choose which vector is appropriate for your use. However, I did not cover all the Flexi® Vectors available. In fact, I saved the HaloTag® Flexi® Vectors for this final installment. Continue reading

How to Use the Flexi® Vectors (Part 1 of 2)

pFC7K (HQ) Flexi® VectorNow that we understand what the numbers, letters and abbreviations mean in the Flexi® Vector naming convention, how does one choose from among the over 40 different vectors? First I will detail the uses for the 21 vectors in the 1–12 range (plus outlier pF25) and address the remaining vectors in a second entry. Continue reading