Dealing with crap to improve water quality: Student builds replica human colon

May 27, 2013
The human colon replica Ian Marcus built to conduct his research. Photo credit: Alicia A. Taylor.

(Phys.org) —To better understand how bacteria impact the environment a former University of California, Riverside graduate student spent nearly a year building a system that replicates a human colon, septic tank and groundwater and "fed" the colon three times a day during weeklong experiments to simulate human eating.

Ian Marcus, who recently earned his Ph.D. from the UC Riverside Bourns College of Engineering, said discussion of the research often left people a bit perplexed.

"People would give a kind-of-interested-but-definitely-don't-talk-about-it-during-dinner look because we're literally dealing with crap," Marcus said. "It has got the smell. It has got everything."

The idea for the project came after Marcus noticed that scientists typically study bacteria in an isolated environment under ideal growing conditions. That presents a problem because bacteria typically proliferate in with other microorganisms such as archaea, and .

Marcus set out to solve that problem by creating a simulated environment where the life cycle of bacteria (he used a pathogenic strain of E. coli in these experiments) and the microbial communities they live in can be studied from the human colon to to .

In the past, researchers have simulated the gut of humans and synthetic aquatic environments, but no one had combined the two, as far as Marcus can tell.

The replica septic tank Ian Marcus built to conduct his research.

By comparing his finding with those of researchers who worked with bacteria in an isolated environment, Marcus found that the E. coli strain in the microbial community may be less mobile in and more prone to biofilm that than the isolated strain.

This means that the E. coli would linger longer in the environment, since biofilm provides a refuge for all the microorganisms within it. When the biofilm matures it sends out bacteria to colonize another surface thus the bacteria could survive in the environment for longer periods of time.

"This means that pathogens could potentially linger longer and over a long period of time travel greater distances in the groundwater," Marcus said.

Marcus said his research shows you should study as close to possible in their natural habitats.

Marcus, who worked in the lab of Sharon Walker, an associate professor of chemical and environmental engineering, had his findings published in a paper called "Linking Microbial Community Structure to Function in Representative Simulated Systems" in the journal Applied Environmental Microbiology. Co-authors were Walker, and Hailey A. Wilder and Shanin J. Quazi, both former students in Walker's lab.

"It is a pleasure to work with a student who can think outside of the box and bring in fresh ideas on how we can approach our research," Walker said. "Ian's work has provided critical new insight into how microbial communities behave in wastewater treatment and contribute to biological contamination of water, which really changes the paradigm of how we do research and manage our water resources."

Explore further: Two-armed control of ATR, a master regulator of the DNA damage checkpoint

Related Stories

A baby, Skype and water research partnership with Israel

Jul 20, 2010

A year ago, Sharon Walker, an associate professor of chemical and environmental engineering at the UC Riverside Bourns College of Engineering, flew to Israel with support from a Fulbright fellowship to study water quality ...

Bacteria use hydrogen, carbon dioxide to produce electricity

May 20, 2013

Researchers have engineered a strain of electricity-producing bacteria that can grow using hydrogen gas as its sole electron donor and carbon dioxide as its sole source of carbon. Researchers at the University of Massachusetts, ...

Recommended for you

Japanese scientist resigns over stem cell scandal

Dec 19, 2014

A researcher embroiled in a fabrication scandal that has rocked Japan's scientific establishment said Friday she would resign after failing to reproduce results of what was once billed as a ground-breaking study on ...

'Hairclip' protein mechanism explained

Dec 18, 2014

Research led by the Teichmann group on the Wellcome Genome Campus has identified a fundamental mechanism for controlling protein function. Published in the journal Science, the discovery has wide-ranging implications for bi ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

Milou
3 / 5 (2) May 27, 2013
Bill Gates Foundation for 3rd world, toilet solution should talk to this guy. This is fantastic because, one thing is certain, with humans there will always be lots of crap! I am surprised we have not done this study before???
Jeddy_Mctedder
2 / 5 (4) May 27, 2013
Genius. This is creativity. Genius

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.