Featured Research

from universities, journals, and other organizations

Toxin produced by bacteria could serve as model for next-generation antibiotics

Date:
November 14, 2013
Source:
Cell Press
Summary:
The recent rise in antibiotic-resistant bacteria is a serious public health threat, and there is a need for new therapeutic strategies to combat these infections. A study has revealed a new toxin that inhibits bacterial growth by blocking the DNA replication machinery, which is not targeted by currently available antibiotics. The findings open new therapeutic avenues for developing the next generation of antibiotics.

This image shows the structure of the E. coli sliding clamp, DnaN, in complex with a peptide from DNA polymerase III (PDB: 3D1F). The toxin SocB likely disrupts this complex to arrest DNA replication by binding a region of DnaN near the residue marked in green.
Credit: Molecular Cell, Aakre et al.

The recent rise in antibiotic-resistant bacteria is a serious public health threat, and there is a need for new therapeutic strategies to combat these infections. A study published by Cell Press on November 14th in the journal Molecular Cell has revealed a new toxin that inhibits bacterial growth by blocking the DNA replication machinery, which is not targeted by currently available antibiotics. The findings open new therapeutic avenues for developing the next generation of antibiotics.

"One source of inspiration for new antibiotic targets is bacteria themselves," says senior study author Michael Laub of the Massachusetts Institute of Technology. "By studying the ways in which toxins produced by bacteria inhibit their growth, we may potentially find clues into targets that hadn't been considered previously."

Bacterial growth is regulated in part by sets of genes known as toxin-antitoxin (TA) systems, each of which typically encodes two proteins -- the toxin and the antitoxin. These proteins normally form a non-toxic complex, but under stressful conditions, the antitoxin degrades and frees up the toxin, which then inhibits bacterial proliferation. Despite the key role TA systems play in regulating bacterial growth, relatively little is known about how they work, and they currently are not targeted by any antibiotics in clinical use.

In the new study, Laub and his team identified a novel TA system called SocAB. Unlike all other known TA systems, SocAB targets bacterial DNA replication machinery. The toxin, SocB, blocks DNA replication and inhibits bacterial growth by interacting with a protein called DnaN, a central hub in protein networks involved in multiple cellular processes. The researchers also pinpointed the region on DnaN that is critical for this interaction. The findings suggest that novel antibiotics that mimic the effects of SocB by targeting this region on DnaN could form the basis of a promising therapeutic strategy in the future.

"Our results reveal unexpected diversity in the molecular mechanisms underlying toxin-antitoxin systems, which are found throughout the bacterial kingdom," Laub says. "Because DnaN is highly conserved between bacteria, targeting this part of the DNA replication machinery may be a generalizable strategy to inhibit bacterial growth."


Story Source:

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


Journal Reference:

  1. Aakre et al. A Bacterial Toxin Inhibits DNA Replication Elongation Through a Direct Interaction with the beta Sliding Clamp. Molecular Cell, November 2013

Cite This Page:

Cell Press. "Toxin produced by bacteria could serve as model for next-generation antibiotics." ScienceDaily. ScienceDaily, 14 November 2013. <www.sciencedaily.com/releases/2013/11/131114122047.htm>.
Cell Press. (2013, November 14). Toxin produced by bacteria could serve as model for next-generation antibiotics. ScienceDaily. Retrieved August 31, 2014 from www.sciencedaily.com/releases/2013/11/131114122047.htm
Cell Press. "Toxin produced by bacteria could serve as model for next-generation antibiotics." ScienceDaily. www.sciencedaily.com/releases/2013/11/131114122047.htm (accessed August 31, 2014).

Share This




More Plants & Animals News

Sunday, August 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Newsy (Aug. 29, 2014) In a new study, a promising experimental treatment for Ebola managed to cure a group of infected macaque monkeys. Video provided by Newsy
Powered by NewsLook.com
Killer Amoeba Found in Louisiana Water System

Killer Amoeba Found in Louisiana Water System

AP (Aug. 28, 2014) State health officials say testing has confirmed the presence of a killer amoeba in a water system serving three St. John the Baptist Parish towns. (Aug. 28) Video provided by AP
Powered by NewsLook.com
Raw: Australian Sheep Gets Long Overdue Haircut

Raw: Australian Sheep Gets Long Overdue Haircut

AP (Aug. 28, 2014) Hoping to break the record for world's wooliest, Shaun the sheep came up 10 pounds shy with his fleece weighing over 50 pounds after being shorn for the first time in years. (Aug. 28) Video provided by AP
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