Painting with Microbes

Extending an Olive Branch – Kyle Callegari, BIOL 342 Sec. 1


Johnny Bravo – Kyle Callegari, BIOL 342 Sec. 1


Yin Yang – Kyle Callegari, BIOL 342 Sec. 1


For the first bacteria plate, on TSA medium, my intent was solely to become more comfortable with streaking a design on a solid medium plate.   I tested adding varied amounts of bacteria and played around with the amount of strokes before swabbing for more bacteria.   I additionally became comfortable using the different sides of the inoculation loop for different width strokes.   The TSA medium is not differential or selective.

The Eosin methylene blue agar is a selective and differential medium used to culture gram-negative bacteria.   Johnny Bravo’s facial features grew a dark purple color indicating rapid lactose fermentation.   This bacteria produces acidic waste quickly and in turn absorbed the dark dye.   The tan strains have remained uncolored because they do not ferment lactose, but rather remove amino acid groups from the lactose medium increasing the pH. I used S. marcescens, and E. aerogenes on this plate My intent with this piece was was to create a recognizable figure that recalls fond memories.

The MacConkey agar is a selective and differential solid medium designed to isolate gram-negative bacteria.   It has dye that indicates the fermentation of lactose by turning pink when the process is occurring.   I used S. marcescens and C. freundii on this plate.   The yin yang symbol represents inseparable and contradictory opposites, and dates back to the third century.   It is possible S. marcescens has a faster growth rate than C. freundii, and that is why the bacteria in pink didn’t establish as well.

1 Comment for “Painting with Microbes”



I showed the TA watching the lab when I went to check on my painting my plates and he said somebody else did Johnny Bravo too, it was you! I was so shocked, how random is that!?

Leave a Reply

Your email address will not be published. Required fields are marked *