Painting with Microbes

Samantha Smith F01

Just a wink and a nudge to my favorite book “East of Eden” by John Steinbeck. I have a a pretty cross stitch of this at home, which admittedly looks a lot better. Perhaps I will stick to my day job and leave the microbe painting to those more artistic than myself.

I used the Eosin Methylene Blue Agar plate for this painting, hoping to achieve a stark different in coloration from the two sources I chose. The lettering and the vine were done with Escherichia coli.  This bacteria is gram negative so is not inhibited by the eosin or methylene blue of the medium. It also produced a deep black color with a metallic green sheen as it ferments lactose with strongly acidic end products. (The green sheen is actually quite pretty, though you can’t tell from the photo). The filigree and leaves are colonies of  Enterobacter aerogenes  which is also gram negative. It produces a pink color because it does ferment lactose, but the end products of fermentation are much less acidic than that of  E. coli.

I would like to add that I had a lot of fun in this assignment and seeing the variety of agar art from the ASM Agar Art Contests.