National Geographic USA - 03.2020

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EXPLORE | DECODER

ART AND CULTURES

ANGELINA HESSE, a Dutch-American

lab assistant and cook, suggested

in the 1880s that an ingredient in

jellies and puddings could be used

to grow bacteria. By finding that pur-

pose for agar, Hesse revolutionized

microbiology and set the stage for a

new art form.

In the laboratory, agar—a gelatinous

substance isolated from seaweed—is

mixed with other nutrients and water,

heated to sterilize, and poured into

shallow dishes. When cooled, it thick-

ens into a smooth, semisolid surface

for bacteria to grow on—an upgrade

from the potatoes, meat extract, and

bread scientists were previously using.

More than a century after Hesse’s

work, agar is still at the center of bac-

terial cultivation. It has also become

BY JENNIFER TSANG

Agar evolved from

a kitchen ingredient

to a lab medium for

growing bacteria.

Now it’s the canvas

for artworks made

of microorganisms.

an unconventional canvas for show-

casing microscopic organisms in all

their visual brilliance.

Some microbes create color natu-

rally. Different species of Streptomyces,

which produces many of our antibiot-

ics, come in pigments ranging from

reds and blues to black. E. coli is natu-

rally a beige color, but introduced genes

can make it or other microbes fluoresce

in bright pinks, greens, and blues. Invis-

ible when first applied to the agar, the

microbes multiply over time to reveal

patterns and colors.

Since 2015, the American Society

for Microbiology (ASM) has held the

annual Agar Art Contest to illuminate

this intersection between science and

art. Every year, says ASM’s Katherine

Lontok, contestants become “more and

more intricate with it, incorporating

things like 3D agar and using spores

and all different kinds of organisms.”

Microbes surround us all the time,

but most are unseen. Agar art reveals

that invisible world, limited only by

the microbial palette and the creator’s

imagination. The contest is “a great

public outreach tool,” Lontok says, and

shows the often overlooked “beauty

and diversity of microbes.”

highlights

of agar art

The Agar Art Contest

proves that “scientists

absolutely can be cre-

ative,” says Katherine

Lontok of the American

Society for Microbiol-

ogy, the sponsor of the

competition. Here, a

sample of 2019 entries;

see more at ngm.com/

mar2020.

This scene of a koi and a lotus

flower, which won first place

in the professional category,

took nine different organisms

to make.

Supreme Court Justice Ruth

Bader Ginsburg—aka RBG—

was painted on an agar known

as VRBG, the acronym for its

chemical components.

This desert scene was made

of pathogens that cause uri-

nary tract infections in “water-

stressed regions like the Middle

East,” the artist says.

an

undersea

scene on

agar

This artwork, “Marine

Universe,” was a finalist

in the professional cat-

egory of the 2019 ASM

contest. To compose

it, Princeton University

student Janie Kim used

microorganisms from

numerous places.

STAPH COLORS

Kim found two of her

pigments very close

at hand: “The white

bacteria, most likely

Staphylococcus epi-

dermidis, and the

yellow bacteria, most

likely Staphylococcus

aureus, were sourced

from my skin,” she says.

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