Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Waves make bug break point

18.12.2001


Formation of the Z ring as an E. coli cell divides.
© Qin Sun/University of Texas


Sloshing proteins help bacteria find their waists.

Chemical waves may help a bacterium to divide by pinpointing its middle, according to a new model of protein interactions1.

Bacteria such as Escherichia coli multiply by dividing. Bacterial division (called binary fission) is simpler than human cell division (mitosis). Human cells erect scaffolding to transport components to the two nascent daughter cells at either end; bacteria just pinch in two.



Within this simplicity lies a puzzle. Without sophisticated molecular machinery, how do bacteria organize themselves so that their daughter cells are of roughly equal size?

Martin Howard of Simon Fraser University in Burnaby, British Columbia, and colleagues think that the key is in the sloshing of three proteins, MinC, MinD and MinE, from end to end of the bacteria. This Min family initiates the formation of a protein drawstring, the Z ring, that runs around the cell’s midpoint and contracts to form a narrow waist.

In an E. coli cell, the Min proteins interact, setting up waves that sweep from end to end with a period of about 1-2 minutes. MinC and MinD gather at the cell’s ends, MinE gathers in the middle. MinC disrupts Z-ring formation, so the ring appears only at the midpoint, where the MinC concentration is low.

Howard’s team has devised a mathematical model of the Min family’s interactions. The model shows that the proteins’ oscillations can produce standing waves, like the air waves in an organ pipe, with MinE concentrated in the cell’s middle and MinC and D at the ends.

A similar interplay between reacting and diffusing proteins during development is thought to be responsible for some animals’ stripes. If Min proteins were coloured, a dividing bacterium would be dark at each end with a light band in the middle.

The researchers say that reasonable assumptions about the rates of protein reactions and diffusion give the right single-band form - two bands of MinE, for example, would result in a cell being pinched into three daughter cells. But they acknowledge that these rates have not yet been measured accurately enough to test the model stringently.

References

  1. Howard, M., Rutenberg, A. D. & de Vet, S. Dynamic compartmentalization of bacteria: accurate division in E. coli. Physical Review Letters, 87, 278102, (2001).

    PHILIP BALL | © Nature News Service
    Further information:
    http://www.nature.com/nsu/011220/011220-7.html

More articles from Life Sciences:

nachricht Show me your leaves - Health check for urban trees
12.12.2017 | Gesellschaft für Ökologie e.V.

nachricht Liver Cancer: Lipid Synthesis Promotes Tumor Formation
12.12.2017 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Long-lived storage of a photonic qubit for worldwide teleportation

12.12.2017 | Physics and Astronomy

Multi-year submarine-canyon study challenges textbook theories about turbidity currents

12.12.2017 | Earth Sciences

Electromagnetic water cloak eliminates drag and wake

12.12.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>