PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

UC Santa Barbara researchers uncover new pathways in bacterial intercellular competition

2013-04-09
(Press-News.org) (Santa Barbara, Calif.) –– There's an epic battle taking place that's not on the national radar: intercellular competition. While it's not an Olympic event, new research from UC Santa Barbara demonstrates that this microscopic rivalry can be just as fierce as humans going for the gold.

Christopher Hayes, UCSB associate professor of molecular, cellular and developmental biology, along with postdoctoral fellow Sanna Koskiniemi, graduate student James Lamoureux, and others, examined the role certain proteins, called rearrangement hotspots (Rhs), play in intercellular competition in bacteria. The findings appear today in the Proceedings of the National Academy of Sciences.

Rhs proteins and related YD-peptide repeat proteins are present in a wide range of bacterial species and other organisms, including human beings, where they help establish communications between neurons in the brain when the visual system is developing. Hayes and his team found that Rhs proteins enable Dickeya dadantii 3937, a phytopathogenic bacterium causing soft rot diseases on many crops, to compete with members of its own kind through touch-dependent killing.

While Rhs have been recognized for more 30 years, their function has been enigmatic. This new research sheds light on the mystery. Rhs proteins possess a central repeat region, characteristically the YD-repeat proteins also found in humans, as well as variable C-terminal sequences, which have toxin activity. C-terminal regions are highly variable between bacterial strains even in the same species, indicating that a wide variety of weapons are deployed.

"Bacteria almost always have a different Rhs toxins," explained Hayes. "No one really knows why, but perhaps the toxins are rapidly evolving, driven by intercellular competition. In essence, these cells are fighting it out with each other. It's like an arms race to see who has the best toxins."

Cellular competition is analogous to that between humans and reflects a scarcity of resources. Like people, bacteria need a place to live and food to eat. "We think these systems are important for bacterial cells to establish a home and defend it against competitors," said Hayes. "In fact, bacteria have many systems for competition. And as we uncover more mechanisms for intercellular competition, we realize this is a fundamental aspect of bacterial biology."

These findings demonstrate that Rhs systems in diverse bacterial species are toxin delivery machines. "We have been able to show that gram-negative (Dickeya dadantii) as well as gram-positive (Bacillus subtilis) bacteria use Rhs proteins to inhibit the growth of neighboring bacteria in a manner that requires cell-to-cell contact," said Koskiniemi, the paper's lead author.

The toxic part of Rhs at the tip (the C-terminal region) is delivered into target cells after cell-to-cell contact. Some toxic tips destroy DNA and others destroy transfer RNA, which is essential for protein synthesis. These toxin activities help the bacteria expressing them to outcompete other members of the same species not carrying an antidote.

This work may help scientists design Rhs-based bacterial probiotics that kill specific pathogens but leave most normal flora unharmed. The research was supported by grants from the National Science Foundation and National Institutes of Health and by fellowships from the Carl Tryggers and Wenner-Gren Foundations.



INFORMATION:



ELSE PRESS RELEASES FROM THIS DATE:

Short daily walk might help teen smokers cut down or quit, new study says

2013-04-09
WASHINGTON—Teenagers who increased the days on which they got just 20 minutes of exercise were able to cut down on their smoking habit. And teenage smokers were more likely to quit altogether if they participated in a smoking cessation/fitness program—and they ramped up the days on which they got at least 30 minutes of physical activity, according to a study published online April 9. "This study adds to evidence suggesting that exercise can help teenagers who are trying to quit smoking," says lead author Kimberly Horn, EdD, the Associate Dean for Research at the George ...

New mouse viruses could aid hepatitis research

2013-04-09
Newly discovered mouse viruses could pave the way for future progress in hepatitis research, enabling scientists to study human disease and vaccines in the ultimate lab animal. In a study to be published in mBio®, the online open-access journal of the American Society for Microbiology, scientists describe their search for viruses related to the human hepatitis C virus (HCV) and human pegiviruses (HPgV) in frozen stocks of wild mice. The discovery of several new species of hepaciviruses and pegiviruses that are closely related to human viruses suggests they might be used ...

Google searches about mental illness follow seasonal patterns

2013-04-09
San Diego, CA, April 9, 2013 – A new study published in the May issue of the American Journal of Preventive Medicine finds that Google searches for information across all major mental illnesses and problems followed seasonal patterns, suggesting mental illness may be more strongly linked with seasonal patterns than previously thought. Monitoring population mental illness trends has been an historic challenge for scientists and clinicians alike. Typically, telephone surveys are used to try to glimpse inside the minds of respondents, but this approach is limited because ...

New genetic link found between normal fetal growth and cancer

2013-04-09
Two researchers at the National Institutes of Health discovered a new genetic link between the rapid growth of healthy fetuses and the uncontrolled cell division in cancer. The findings shed light on normal development and on the genetic underpinnings of common cancers. The work, conducted using mouse and human tissue, appears in today's issue of the Proceedings of the National Academy of Sciences. The authors, Julian C. Lui, Ph.D., and Jeffrey Baron, M.D., work at the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). "We've long ...

Update on federal estate laws and impact on Connecticut estates

2013-04-09
Update on federal estate laws and impact on Connecticut estates Article provided by Riefberg, Smart, Donohue & NeJame, P.C. Visit us at http://www.rsdn.com The new federal estate tax rules for 2013 were passed during the fiscal cliff negotiations. This portion of the negotiations included an exclusion of up to $5.25 million in assets per person. This means each person can pass just over $5 million in assets to loved ones without paying taxes and each couple can exclude $10.5 million. This new amount is much larger than originally anticipated. Without the ...

Understanding protection from pregnancy discrimination in California

2013-04-09
Understanding protection from pregnancy discrimination in California Article provided by Larabee Law Firm Visit us at http://www.larabeelaw.com Too often expecting mothers face bias and discrimination in the workplace. Federal law affords pregnant workers protection from being treated differently than other employees in the workplace, and federal law also provides an amount of unpaid leave time for certain working mothers and fathers with newborns. However, pregnant workers in California are given even greater rights under state law. According to the National ...

Computer crimes carry harsh penalties

2013-04-09
Computer crimes carry harsh penalties Article provided by James S. Friedman, LLC Visit us at http://www.jfriedlawfirm.com The internet has changed the way we live. It has made it incredibly easy for individuals to stay connected with one another, even during the busiest of times. Many people work in occupations that depend on the internet to assist in the completion of daily tasks. Communities nationwide have realized how important it is to allow residence to have the systems in place that permit internet access. Most people use the internet for news and entertainment, ...

Warranties protect California consumers

2013-04-09
Warranties protect California consumers Article provided by The Law Offices of Michael S. Humphries Visit us at http://www.lemoncarsrus.com Californians might be aware that as buyers they have certain protections under the law. For example, they may have heard of California's "lemon law" that covers the purchase of a motor vehicle. Other kinds of purchases in California are also subject to consumer protections such as warranty laws. "Lemon law" provisions People who buy or lease a new vehicle in California have legal recourse if the vehicle ...

Chapter 7 versus Chapter 13 bankruptcy: Which is right for you?

2013-04-09
Chapter 7 versus Chapter 13 bankruptcy: Which is right for you? Article provided by James C. Warr & Associates, PLC Visit us at http://www.go2warr.com In these tough economic times, thousands of Americans are finding themselves overwhelmed by debt. While it is always a challenge to overcome financial difficulties, there are built in protections in the U.S. Bankruptcy Code that can help you wipe out your debt and get a fresh financial start. Yet, even though almost everyone has heard of bankruptcy, not all consumers are familiar with the types of bankruptcy ...

Researchers identify signs of brain damage in living NFL veterans

2013-04-09
Researchers identify signs of brain damage in living NFL veterans Article provided by The Law Offices of Michael Goldstein Visit us at http://www.brainspinalcordinjuryattorneysandiego.com Researchers at the University of California, Los Angeles made an important breakthrough recently when they identified signs of potentially crippling brain damage in five former professional football players. The research involved performing brain scans on a group of former NFL players. In five of the players, scans revealed images of a telltale protein associated with a type ...

LAST 30 PRESS RELEASES:

Fig trees convert atmospheric CO2 to stone

Intra-arterial tenecteplase for acute stroke after successful endovascular therapy

Study reveals beneficial microbes that can sustain yields in unfertilized fields

Robotic probe quickly measures key properties of new materials

Climate change cuts milk production, even when farmers cool their cows

Frozen, but not sealed: Arctic Ocean remained open to life during ice ages

Some like it cold: Cryorhodopsins

Demystifying gut bacteria with AI

Human wellbeing on a finite planet towards 2100: new study shows humanity at a crossroads

Unlocking the hidden biodiversity of Europe’s villages

Planned hydrogen refuelling stations may lead to millions of euros in yearly losses

Planned C-sections increase the risk of certain childhood cancers

Adults who have survived childhood cancer are at increased risk of severe COVID-19

Drones reveal extreme coral mortality after bleaching

New genetic finding uncovers hidden cause of arsenic resistance in acute promyelocytic leukemia

Native habitats hold the key to the much-loved smashed avocado’s future

Using lightning to make ammonia out of thin air

Machine learning potential-driven insights into pH-dependent CO₂ reduction

Physician associates provide safe care for diagnosed patients when directly supervised by a doctor

How game-play with robots can bring out their human side

Asthma: patient expectations influence the course of the disease

UNM physician tests drug that causes nerve tissue to emit light, enabling faster, safer surgery

New study identifies EMP1 as a key driver of pancreatic cancer progression and poor prognosis

XPR1 identified as a key regulator of ovarian cancer growth through autophagy and immune evasion

Flexible, eco-friendly electronic plastic for wearable tech, sensors

Can the Large Hadron Collider snap string theory?

Stuckeman professor’s new book explores ‘socially sustainable’ architecture

Synthetic DNA nanoparticles for gene therapy

New model to find treatments for an aggressive blood cancer

Special issue of Journal of Intensive Medicine analyzes non-invasive respiratory support

[Press-News.org] UC Santa Barbara researchers uncover new pathways in bacterial intercellular competition