The 5 Stages of Failed Cloning Grief (and how to get back on track!)

Cloning is a fickle process that can make even the most seasoned bench scientists scream in frustration. By the time you perform a colony PCR and run the gel to check for your insert, you’ve invested several days in preparing these transformed cells. But then, the unthinkable happens. When you image your gel…the target band is missing.

This can trigger what’s known as “The 5 Stages of Failed Cloning Grief.” As you work through each stage at your own pace, just know that scientists all over the world feel your pain and can empathize with you in this difficult time. Continue reading “The 5 Stages of Failed Cloning Grief (and how to get back on track!)”

Bacterial transformation and counting colonies for grade school students

Our experimental setup: Microbe plushies, Lego DNA, plates, iPhones and makeshift stand, ready to go.
Our experimental setup: Microbe plushies, Lego DNA, plates, iPhones and makeshift stand, ready to go.
A few weeks ago, our elementary school held its annual science fair. Owing to the greater-than-usual number of scientists among the parents, the halls of this event were lined with tables staffed by said parents, showing off the wonders of science, tech, and especially biotech. There were at least three stations devoted to various aspects of stem cell research, and the table next to us had kids run simple nucleic acid extractions from wheat germ using detergent and alcohol – my son loved that one, as he pulled out the stringy goop with a q-tip at the end of the process.

My wife and I contributed to the festivities by putting together a presentation on bacterial transformation. I was just about finished working on a colony counter iPhone® app for Promega, so I figured why not try it out in the field: Print out some colorful ersatz bacterial plates, have the kids count the colonies using the app (yay, touch screens!) and maybe teach them something about genetic engineering along the way.

Our setup turned out to be a lot of fun to run, and quite popular to boot. It went roughly like this: Continue reading “Bacterial transformation and counting colonies for grade school students”

Now Available for Purchase: Promega Colony Counter App

colony counterDo you count colonies on agar plates? Do you often need to average counts over a series of plates? The Promega Colony Counter app for iPhone® (3GS, 4S, and 5) and iPod® Touch (4th and 5th generation) allows you to take a picture of your plate, obtain a good first-guess count and refine it quickly by marking additional colonies and masking areas where the app may have over-counted.

The app is available for purchase for 3.99 USD from the iTunes store in North America and Europe.

Efficient Cloning and Expression of High Protein Yields Using KRX Cells

Escherichia coli remains the first choice of many researchers for producing recombinant protein for functional studies due to its ease of use, well established protocols, rapid cell growth and low cost of culturing. Researchers often need to clone using an E. coli host with good transformation characteristics first, then transfer the desired clone to the expression host. We have developed a new E. coli host KRX, that provides protein yields comparable to those of BL21(DE3) but with much higher transformation efficiencies. Continue reading “Efficient Cloning and Expression of High Protein Yields Using KRX Cells”