Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bioengineers Fill Holes in Cellular Self-Organization

08.10.2008
The chemical and biological aspects of cellular self-organization are well-studied; less well understood is how cell populations order themselves biomechanically – how their behavior and communication are affected by high density and physical proximity.

Bioengineers and physicists at the University of California San Diego, in a paper published in the current issue of the Proceedings of the National Academy of Sciences, have begun to address these fundamental questions.

The UC San Diego scientists focused their research on dense colonies of the rod-shaped bacteria Escherichia coli. By analyzing the spatial organization of the bacteria in a microfluidic chemostat – a kind of mini-circuit board for liquids rather than electrons – they found that growth and expansion of a dense colony of cells leads to a dynamic change from relative disorder to a remarkable re-orientation and alignment of the rod-like cells.

That finding, described in their paper “Biomechanical Ordering of Dense Cell Populations,” allowed them to develop a model of collective cell dynamics, and to use this model to “elucidate the mechanism of cell ordering, and quantify the relationship between the dynamics of cell proliferation and the spatial structure of the population.”

One of the authors, Lev S. Tsimring, at UC San Diego’s Institute of Nonlinear Science, explained the bioengineers’ use of bacteria to study the biomechanical ordering of cells.

“When environmental conditions are harsh, bacteria like to stick together. The most typical form of bacterial organization in nature is a biofilm: a dense quasi-two-dimensional colony of bacteria. Biofilms grow in and on living tissues, the surfaces of rocks and soils, and in aquatic environments,” he said, “but they’re also found in man-made systems and devices such as industrial piping and artificial implants. And bacteria are known to actively migrate toward surfaces and small cavities, where they form high-density colonies.”

At low densities, he said, bacteria and other cells communicate “remotely” by sending chemical signals – “chemotaxis” – but, as they aggregate and form dense communities, direct biomechanical contacts play a bigger and bigger role in how they organize themselves.

“Although previous studies have explored the complex signaling mechanisms in the early stages of biofilm formation,” Tsimring said, “the biomechanics of direct cellular contacts have received little attention. We focused, therefore, on the structure and dynamics of a growing two-dimensional colony of non-motile bacteria.”

His fellow researcher, Jeff Hasty, at the Institute for Nonlinear Science and UC San Diego’s Department of Bioengineering, said the team’s work provides a multiscale description of cell colony growth.

“Our results reveal how cell growth and colony expansion trigger the formation of the orientational order in the population,” Hasty said, “which, in turn, affects the mechanical and biochemical properties of the colony.”

The details of their research, the authors say, helps scientists understand how the local interaction of elementary components leads to collective behavior and the formation of a highly organized system.

Tsimring and Hasty collaborated with Scott Cookson, of the Department of Bioengineering, and Dmitri Volfson, now at Rosetta Inpharmatics LLC.

Funding for the research was provided by the National Institutes of Health, the National Science Foundation, and UC MEXUS-CONACYT.

Paul K. Mueller | Newswise Science News
Further information:
http://www.ucsd.edu

More articles from Life Sciences:

nachricht O2 stable hydrogenases for applications
23.07.2018 | Max-Planck-Institut für Chemische Energiekonversion

nachricht Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

The Maturation Pattern of the Hippocampus Drives Human Memory Deve

23.07.2018 | Science Education

FAU researchers identify Parkinson's disease as a possible autoimmune disease

23.07.2018 | Health and Medicine

O2 stable hydrogenases for applications

23.07.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>