Featured Research

from universities, journals, and other organizations

How Proteins Control The Process When Bacteria Multiply: May Lead To New Antibiotics

Date:
April 11, 2008
Source:
Johns Hopkins University
Summary:
A team has solved important puzzles concerning how certain proteins guide the reproduction of bacteria. Solving the Z ring's mysteries may lead to new antibiotics.

A team led by Johns Hopkins researchers has solved important puzzles concerning how certain proteins guide the reproduction of bacteria, discoveries that could lead to a new type of antibiotics.

In a recent study published in the journal Current Biology, the scientists reported how a belt-like structure called a Z ring, which pinches a rod-shaped bacterium to produce two offspring, can be disabled by a protein called MinC. By exploiting this vulnerability, the researchers said, pharmaceutical companies may find a way to fight infections that no longer respond to older medications.

"The potential medical applications of our discovery are significant," said Alex Dajkovic, lead author of the paper. "Because the molecules involved in cell division are very similar in almost all bacteria, the process we uncovered provides a new target for the people who make antibiotics. This is extremely important because antibiotic resistance is on the rise, and many preventable deaths, especially in the developing world, are caused by bacterial infections."

Dajkovic helped make the discoveries as a postdoctoral fellow in the lab of Denis Wirtz, a professor of chemical and biomolecular engineering in Johns Hopkins' Whiting School of Engineering. Dajkovic is now a researcher at Institut Curie in Paris.

Wirtz, who also is associate director of the Johns Hopkins Institute for NanoBioTechnology, noted that "most antibiotics target the ability of bacteria to build their cell walls or their ability to make proteins or DNA. With this paper, Alex and the rest of the team identified new molecular targets that could disrupt bacterial cell division. If the bacteria can't reproduce, the infection will die."

The researchers focused on the rod-shaped bacterium E. coli, commonly found in the human digestive tract, which serves as a model organism for study of basic bacterial processes. When these single-celled microbes want to multiply, a structure called the Z ring forms, then begins to tighten like a rubber band around each bacterium's midsection. The Z ring helps to pinch the rod-shaped body into two microbial sausages that finally split apart to form two cells.

For about 20 years, researchers have known about the Z ring but have not understood precisely how it operated and why it always formed in the middle of rod-shaped cells. The main components of Z rings are filaments of a protein molecule called FtsZ

In the new journal article, the Johns Hopkins-led researchers were able to report for the first time that the changing of FtsZ threads from a liquid-like form to a more solid structure inside the cell is important for the formation of the Z ring. The team found that FtsZ threads weave themselves into a framework or scaffold that can hold all of the other molecules involved in the cell division process. The FtsZ filments are able to weave this tapestry, the researchers learned, because they tend to attract one another and interact along the length of each thread.

The team also discovered that MinC, another protein inside the bacterial cell, disrupts this process by liquefying the structure that is used to form a Z ring. "MinC blocks the attraction between FtsZ filaments along their lengths, and it also makes the filaments more fragile," said Dajkovic. "This has the effect of shearing the weavings in the tapestry of the Z ring, which causes the whole structure to fall apart."

MinC is most prevalent on the outer ends of the rod-shaped bacterial cell, the researchers said, and this explains why the Z ring always forms and splits the cell in the middle, where it is less likely to encounter its protein foe. The team members said this discovery also presents a promising opportunity: a new drug that mimics the effects of MinC could play havoc with the bacterial reproductive process and thereby put an end to an infection.

The findings resulted from a collaboration involving Dajkovic, whose background is in cell biology and biochemistry; Wirtz, whose expertise is in biophysics and engineering; and Sean X. Sun, a Johns Hopkins assistant professor of mechanical engineering who provided computational modeling of the cell division process. Wirtz and Sun were co-authors of the Current Biology paper, along with Ganhui Lan, a doctoral student in Sun's lab, and Joe Lutkenhaus, a University Distinguished Professor in the Department of Microbiology, Molecular Genetics and Immunology at the University of Kansas Medical Center. Lutkenhaus was Dajkovic's faculty advisor as a doctoral student.

The research was supported by grants from the National Institutes of Health.


Story Source:

The above story is based on materials provided by Johns Hopkins University. Note: Materials may be edited for content and length.


Cite This Page:

Johns Hopkins University. "How Proteins Control The Process When Bacteria Multiply: May Lead To New Antibiotics." ScienceDaily. ScienceDaily, 11 April 2008. <www.sciencedaily.com/releases/2008/04/080408105816.htm>.
Johns Hopkins University. (2008, April 11). How Proteins Control The Process When Bacteria Multiply: May Lead To New Antibiotics. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2008/04/080408105816.htm
Johns Hopkins University. "How Proteins Control The Process When Bacteria Multiply: May Lead To New Antibiotics." ScienceDaily. www.sciencedaily.com/releases/2008/04/080408105816.htm (accessed April 24, 2014).

Share This



More Plants & Animals News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Fungus Killing Bats, Spreading in US

Deadly Fungus Killing Bats, Spreading in US

AP (Apr. 24, 2014) A disease that has killed more than six million cave-dwelling bats in the United States is on the move and wildlife biologists are worried. White Nose Syndrome, discovered in New York in 2006, has now spread to 25 states. (April 24) Video provided by AP
Powered by NewsLook.com
Blood From World's Oldest Woman Suggests Life Limit

Blood From World's Oldest Woman Suggests Life Limit

Newsy (Apr. 24, 2014) Scientists say for the extremely elderly, their stem cells might reach a state of exhaustion. This could limit one's life span. Video provided by Newsy
Powered by NewsLook.com
Raw: Kangaroo Rescued from Swimming Pool

Raw: Kangaroo Rescued from Swimming Pool

AP (Apr. 24, 2014) A kangaroo was saved from drowning in a backyard suburban swimming pool in Australia's Victoria state on Thursday. Australian broadcaster Channel 7 showed footage of the kangaroo struggling to get out of the pool. (April 24) Video provided by AP
Powered by NewsLook.com
Could Marijuana Use Lead To Serious Heart Problems?

Could Marijuana Use Lead To Serious Heart Problems?

Newsy (Apr. 24, 2014) A new study says marijuana use could lead to serious heart-related complications. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins