Cosmid Pics -

Before diving into the images, let’s align on the subject. A cosmid is a hybrid plasmid that contains the of bacteriophage lambda. This clever design allows cosmids to be packaged into phage heads in vitro, then infect E. coli and propagate as plasmids.

This is where cosmid pics get visually striking. After plating a cosmid library, researchers lift colonies onto nylon membranes, lyse them, and probe with a radioactive or chemiluminescent label. cosmid pics

sites that allow large DNA chunks (up to 45kb!) to be packaged into viral heads. Before diving into the images, let’s align on the subject

The Allen Lab at Stanford (fictionalized example) spent three months failing to isolate a 40 kb insert for a CRISPR delivery vector. They kept obtaining 15 kb inserts. One glance at their cosmid pic — a restriction digest gel — showed an extra 2.8 kb band in every clone. That band matched the vector’s stuffer fragment. The problem? Incomplete digestion of the stuffer during library construction. The visual evidence allowed them to redesign their partial Sau3AI digestion protocol, and they succeeded on the next attempt. coli and propagate as plasmids

If you need to compare your results or create a mock-up for a presentation, these databases offer verified cosmid pics:

Tag your best cosmids with #CosmidPics — I’ll feature the weirdest ones next week.