Constellations in my Borrelia

So, do any of you ever wonder what I do when I’m in my Lyme Studies lab?

I know, you have been dying to know!

Mostly I count Borrelia burgdorferi, the primary bacteria responsible for Lyme disease in the U.S.  There are other Borrelia species that also cause Lyme disease, but most are not found in my neck of the woods.

In general Borrelia are thin spiral shaped bacteria that swim about independently.  However, they do also form clusters of varying size.  I don’t know why for sure, and I don’t know if anyone else does either.  They might and I just haven’t stumbled on that information yet.

Anyway, I am responsible for a strain that has been genetically engineered to express a green fluorescent protein that makes it glow green.  This has many practical applications, it makes them much easier to see for sure, it also makes it easier to tell if the bacteria is alive as dead bacteria don’t make glowing green protein, they don’t make anything if they are dead.

So every week I gaze into a microscope and check for itsy-bitsy green lines on a field of black.  A healthy bacteria culture has millions or even billions of the little critters all swirling about doing their little bacteria thing.  Often there are so many it looks like the depths of outer space, if the stars, planets, galaxies and nebulae were all fluorescent green anyway.  To see them well it is best to turn off the lights in the lab to reduce the ambient light which can interfere with catching a glimpse of the faint green glow, so it really does often feel like star gazing through binoculars.  The other day it so strongly put me in mind of star gazing that I started looking for shapes in the “constellations” of bacteria.

Lo an behold I found Ursa Major!

I think I just discovered the evolution of Bear-relia!

Random fact and a mini science lecture

Two hours.

That’s how long it takes to count 5,500,000 Borrelia burgdorferi, which are the microscopic bacteria that cause Lyme disease.

Being microscopic, you need to view them under a magnification of at least 400 times and even still they look like wispy, kinky fine hairs.  For the super curious, they are only about 0.2-0.3 micrometers in diameter and can be up to 20 micrometers long.

They look sort of like this:

I don’t know the magnification of this image I stole from Google images, but they look bigger in this photo than they do on the scope I use in the lab, so I’m guessing this is in excess of 400 x magnification.

Now, if you’ve never worked with microscopic stuff before, you might wonder how do you count 5 and a half million of some uber-tiny critter?

Well, you don’t actually count them one by one.  That would be crazy and nigh impossible.  You use science math.  And, a special slide called a Petroff-Hausser Counting Chamber.  It was actually made for counting sperm, but works for any super tiny microscopic thing.  It looks vaguely like this this photo I also stole from Google images:

You place 5 microliters of your sample (sometimes you even dilute that, because a lot of microscopic critters can be suspended in even just 5 microliters), on the slide.  It has microscopic grid lines on it.  Then you count all the Borrelia in the grid.  Using science math you can then calculate how many of these guys you would have in a milliliter.  It actually is pretty easy.

What took so long is that I had to count nine different samples.  Which means not only did I have to count the little buggers nine different times, but I had to prepare 9 dilutions, and clean the slide between each sample.

I’ll be doing this a lot.  Maybe I’ll get faster.

Or maybe I’ll go cross-eyed.