How Does One Capture a Phage?

Phage are everywhere —- some estimate that they constitute the greatest biomass on Earth.  Although ubiquitous, you must expend some effort to isolate one.  How does one capture a phage?  This summer, while I was at Janelia Farm, the research campus of HHMI, undergoing training for instructing the lab course, I phoned home to check in after the first day.  My seven-year-old daughter asked what I was doing, and when I explained that my goal was to isolate a phage — and that it was something we could even do together — she excitedly asked for details.  As I started to describe the process, she interrupted me — she ran to get the piece of cardboard shown in the photo, and started to take notes.

She wrote:

1.  get a tube

2.  get some dirt and put it in the tube

3.  add some water  mix it up

4.  let it sit

5.  filter it

6.  take some of the likwid

7.  and add it to some backtria

8.  grow the backtria

9.  if the backtira does not grow it is a (phage)

Some of the spelling is phonetic, but she describes the process well.  If in your soil sample you have phage, and the phage are capable of infecting (and lysing) the bacteria, the phage leave a small clear spot, called a plaque, in a lawn, or plateful, of bacteria.  In the header for this blog, you see plaques on the left that are caused by a phage that I isolated at Janelia Farm.  And if I characterize the phage and show that it is unique, I’ve promised my daughter the naming rights.  She’s pretty excited.  I expect, though, I’ll need to produce something more for her birthday.