Corporate Banner
Satellite Banner
Scientific Communities
Become a Member | Sign in
Home>News>This Article

Researchers Find that Going with the Flow Makes Bacteria Stick

Published: Tuesday, February 25, 2014
Last Updated: Monday, February 24, 2014
Bookmark and Share
In surprising new discovery, scientists show that microbes are more likely to adhere to tube walls when water is moving.

In a surprising new finding, researchers have discovered that bacterial movement is impeded in flowing water, enhancing the likelihood that the microbes will attach to surfaces. The new work could have implications for the study of marine ecosystems, and for our understanding of how infections take hold in medical devices.

The findings, the result of microscopic analysis of bacteria inside microfluidic devices, were made by MIT postdoc Roberto Rusconi, former MIT postdoc Jeffrey Guasto (now an assistant professor of mechanical engineering at Tufts University), and Roman Stocker, an associate professor of civil and environmental engineering at MIT. Their results are published in the journal Nature Physics.

The study, which combined experimental observations with mathematical modeling, showed that the flow of liquid can have two significant effects on microbes: “It quenches the ability of microbes to chase food,” Stocker says, “and it helps microbes find surfaces.”

That second finding could be particularly beneficial: Stocker says in some cases, that phenomenon could lead to new approaches to tuning flow rates to prevent fouling of surfaces by microbes - potentially averting everything from bacteria getting a toehold on medical equipment to biofilms causing drag on ship hulls.

The effect of flowing water on bacterial swimming was “a complete surprise,” Stocker says.

“My own earlier predictions of what would happen when microbes swim in flowing water had been: ‘Nothing too interesting,’” he adds. “It was only when Roberto and Jeff did the experiments that we found this very strong and robust phenomenon.”

Even though most microorganisms live in flowing liquid, most studies of their behavior ignore flow, Stocker explains. The new findings show, he says, that “any study of microbes suspended in a liquid should not ignore that the motion of that liquid could have important repercussions on the microbes.”

The novelty of this result owes partly to the divisions of academic specialties, and partly to advances in technology, Stocker says. “Microbiologists have rarely taken into account fluid flow as an ecological parameter, whereas physicists have just recently started to pay attention to microbes,” he says, adding: “The ability to directly watch microbes under the controlled flow conditions afforded by microfluidic technology - which is only about 15 years old - has made all the difference in allowing us to discover and understand this effect of flow on microbes.”

The team found that swimming bacteria cluster in the “high shear zones” in a flow - the regions where the speed of the fluid changes most abruptly. Such high shear zones occur in most types of flows, and in many bacterial habitats. One prominent location is near the walls of tubes, where the result is a strong enhancement of the bacteria’s tendency to adhere to those walls and form biofilms.

But this effect varies greatly depending on the speed of the flow, opening the possibility that the rate of biofilm formation can be tweaked by increasing or decreasing flow rates.

Guasto says the new understanding could help in the design of medical equipment to reduce such infections: Since the phenomenon peaks at particular rates of shear, he says, “Our results might suggest additional design criteria for biomedical devices, which should operate outside this range of shear rates, when possible - either faster or slower.”

“Biofilms are found everywhere,” Rusconi says, adding that the majority of bacteria spend significant fractions of their lives adhering to surfaces. “They cause major problems in industrial settings,” such as by clogging pipes or reducing the efficiency of heat exchangers. Their adherence is also a major health issue: Bacteria concentrated in biofilms are up to 1,000 times more resistant to antibiotics than those suspended in liquid.

The concentration of microbes in the shear zones is an effect that only happens with those that can control their movements. Nonliving particles of similar size and shape show no such effect, the team found, nor do nonmotile bacteria that are swept along passively by the water. “Without motility, bacteria are distributed everywhere and there is no preferential accumulation,” Rusconi says.

The new findings could also be important for studies of microbial marine ecosystems, by affecting how bacteria move in search of nutrients when one accounts for the ubiquitous currents and turbulence, Stocker says. Though they only studied two types of bacteria, the researchers predict in their paper that “this phenomenon should apply very broadly to many different motile microbes.”

In fact, the phenomenon has no inherent size limit, and could apply to a wide range of organisms, Guasto says. “There’s really nothing special about bacteria compared to many other swimming cells in this respect,” he says. “This phenomenon could easily apply to a wide range of plankton and sperm cells as well.”

Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,800+ scientific posters on ePosters
  • More Than 4,000+ scientific videos on LabTube
  • 35 community eNewsletters

Sign In

Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Biomedical Imaging at One-Thousandth the Cost
Mathematical modeling enables $100 depth sensor to approximate the measurements of a $100,000 piece of lab equipment.
Tuesday, November 24, 2015
Game for Climate Adaptation
MIT-led project shows a new method to help communities manage climate risks.
Friday, November 06, 2015
Using Ultrasound to Improve Drug Delivery
New approach could aid in treatment of inflammatory bowel disease.
Friday, October 23, 2015
Drug-Resistance Mechanism in Tumor Cells Unravelled
Targeting the RNA-binding protein that promotes resistance could lead to better cancer therapies.
Friday, October 23, 2015
Quantum Physics Meets Genetic Engineering
Researchers use engineered viruses to provide quantum-based enhancement of energy transport.
Friday, October 16, 2015
Messing With The Monsoon
Manmade aerosols can alter rainfall in the world’s most populous region.
Friday, October 02, 2015
A Natural Light Switch
MIT scientists identify and map the protein behind a light-sensing mechanism.
Tuesday, September 29, 2015
Biologists Find Unexpected Role for Amyloid-Forming Protein
Yeast protein could offer clues to how Alzheimer’s plaques form in the brain.
Monday, September 28, 2015
How Flu Viruses Gain The Ability To Spread
New study reveals the soft palate is a key site for evolution of airborne transmissibility.
Friday, September 25, 2015
Viruses Join Fight Against Harmful Bacteria
Engineered viruses could combat human disease and improve food safety.
Friday, September 25, 2015
Targeting DNA
Protein-based sensor could detect viral infection or kill cancer cells.
Tuesday, September 22, 2015
Targeting DNA
Protein-based sensor could detect viral infection or kill cancer cells.
Tuesday, September 22, 2015
Personalized Heart Models For Surgical Planning
System can convert MRI scans into 3D-printed, physical models in a few hours.
Friday, September 18, 2015
Learning About Human Health Using Sewage
PhD student Mariana Matus studies human waste to understand individual and community health.
Thursday, September 17, 2015
Intensity of Desert Storms May Affect Ocean Phytoplankton
MIT study finds phytoplankton are extremely sensitive to changing levels of desert dust.
Tuesday, September 01, 2015
Scientific News
High Throughput Mass Spectrometry-Based Screening Assay Trends
Dr John Comley provides an insight into HT MS-based screening with a focus on future user requirements and preferences.
Kitchen Utensils Can Spread Bacteria Between Foods
In a recent study researchers found that produce that contained bacteria would contaminate other produce items through the continued use of knives or graters—the bacteria would latch on to the utensils commonly found in consumers' homes and spread to the next item.
Exploring the Causes of Cancer
Queen's research to understand the regulation of a cell surface protein involved in cancer.
Safer, Faster Way To Remove Pollutants From Water
Using nanoparticles filled with enzymes proves more effective than current methods.
Drug May Prevent Life-Threatening Muscle Loss in Advanced Cancers
New data describes how an experimental drug can stop life-threatening muscle wasting (cachexia) associated with advanced cancers and restore muscle health.
Ancient Viral Molecules Essential for Human Development
Genetic material from ancient viral infections is critical to human development, according to researchers at the Stanford University School of Medicine.
Novel Tumor Treatment
In the first published results from a $386,000 National Cancer Institute grant awarded earlier this year, a paper by Scott Verbridge and Rafael Davalos has been published.
Speeding Up the Process of Making Vaccines
System uses a freeze-dry concept to develop "just-add-water" solution.
Chemical Design Made Easier
Rice University scientists prepare elusive organocatalysts for drug and fine chemical synthesis.
New Analysis Technique for Chiral Activity in Molecules
Professor Hyunwoo Kim of the Chemistry Department and his research team have developed a technique that can easily analyze the optical activity of charged compounds by using nuclear magnetic resonance (NMR) spectroscopy.
Scroll Up
Scroll Down
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,800+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,000+ scientific videos