Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

How Bacteria Control Their Size

07.01.2015

By monitoring thousands of individual bacteria scientists discovered how they maintain their size from generation to generation

Scientists have traditionally studied bacteria in large numbers, not individually. Working with tens of millions of cells in a culture flask, they tracked their growth by looking at how much the cells dimmed light passing through a tube.


CDC

Methicillin-resistant Staphylococcus aureus, or MRSA, are so uniform in size they look like they were made in a factory. How do the bacteria manage to keep their size so uniform?

Using this method, scientists learned that populations of bacteria grow exponentially, doubling in mass at regular time intervals. And so, not unreasonably, they assumed that individual cells would do the same, dividing only when they have doubled in size.

In the Dec. 24 online issue of Current Biology a group of scientists led by Suckjoon Jun of the University of California-San Diego, and including Petra Levin, PhD, associate professor of biology in Arts & Sciences at Washington University in St. Louis, report that this hypothesis was incorrect.

“Even though on average it is true that mass doubles,” Levin said, “when you look at individual cells it becomes apparent that something else is going on.” Instead of examining populations of cells growing in a flask or test tube, the Jun group instead used a microfluidics device called a “mother machine” to follow hundreds of thousands of individual cells from birth to division.

They found that rather than doubling in size every generation, each cell added the same volume (or mass; the term reflects the measurement technique). Crucially a cell that was small added the same volume as a cell that was large.

Why is this the rule? “Although this might seem counter-intuitive, over many generations this rule ensures that cells in a population maintain a constant size,” Levin said.

“This study really shows how new technologies, in this case the development of the ‘mother machine’ to visualize single bacteria in real time, can lead to new and unexpected answers to old problems,” Levin said.

“Pinning down the growth rule is important,” she added, “because it provides clues to the underlying biochemical mechanism that ultimately controls growth. The mechanism is probably essential — or nearly so — and thus good target for new antimicrobials.”

“Surprisingly little is known about biological size control in general,” Levin said.

“Why are we the size we are? Why are our organs the size they are? Why are the cells in those organs a stereotypical size? What regulates that?”

“We take all this for granted,” she said, “but really, very little of it is understood.”

Contact Information
Diana Lutz
Senior Science Editor
dlutz@wustl.edu
Phone: 314-935-5272

Diana Lutz | newswise
Further information:
http://www.wustl.edu

More articles from Life Sciences:

nachricht Turning carbon dioxide into liquid fuel
06.08.2020 | DOE/Argonne National Laboratory

nachricht Tellurium makes the difference
06.08.2020 | Friedrich-Schiller-Universität Jena

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: ScanCut project completed: laser cutting enables more intricate plug connector designs

Scientists at the Fraunhofer Institute for Laser Technology ILT have come up with a striking new addition to contact stamping technologies in the ERDF research project ScanCut. In collaboration with industry partners from North Rhine-Westphalia, the Aachen-based team of researchers developed a hybrid manufacturing process for the laser cutting of thin-walled metal strips. This new process makes it possible to fabricate even the tiniest details of contact parts in an eco-friendly, high-precision and efficient manner.

Plug connectors are tiny and, at first glance, unremarkable – yet modern vehicles would be unable to function without them. Several thousand plug connectors...

Im Focus: New Strategy Against Osteoporosis

An international research team has found a new approach that may be able to reduce bone loss in osteoporosis and maintain bone health.

Osteoporosis is the most common age-related bone disease which affects hundreds of millions of individuals worldwide. It is estimated that one in three women...

Im Focus: AI & single-cell genomics

New software predicts cell fate

Traditional single-cell sequencing methods help to reveal insights about cellular differences and functions - but they do this with static snapshots only...

Im Focus: TU Graz Researchers synthesize nanoparticles tailored for special applications

“Core-shell” clusters pave the way for new efficient nanomaterials that make catalysts, magnetic and laser sensors or measuring devices for detecting electromagnetic radiation more efficient.

Whether in innovative high-tech materials, more powerful computer chips, pharmaceuticals or in the field of renewable energies, nanoparticles – smallest...

Im Focus: Tailored light inspired by nature

An international research team with Prof. Cornelia Denz from the Institute of Applied Physics at the University of Münster develop for the first time light fields using caustics that do not change during propagation. With the new method, the physicists cleverly exploit light structures that can be seen in rainbows or when light is transmitted through drinking glasses.

Modern applications as high resolution microsopy or micro- or nanoscale material processing require customized laser beams that do not change during...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“Conference on Laser Polishing – LaP 2020”: The final touches for surfaces

23.07.2020 | Event News

Conference radar for cybersecurity

21.07.2020 | Event News

Contact Tracing Apps against COVID-19: German National Academy Leopoldina hosts international virtual panel discussion

07.07.2020 | Event News

 
Latest News

Rare Earth Elements in Norwegian Fjords?

06.08.2020 | Earth Sciences

Anode material for safe batteries with a long cycle life

06.08.2020 | Power and Electrical Engineering

Turning carbon dioxide into liquid fuel

06.08.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>