 |
|
Poison digs its own grave
December 16, 2004Botrytis cinerea (grey mould) has a large arsenal of molecular pumps at its disposal to protect it against toxic substances such as antibiotics, plant defence compounds and fungicides. Dutch researcher Henk-jan Schoonbeek saw how the fungus started to pump out certain toxic substances within just 15 minutes.
Botrytis cinerea causes rot in fruit and vegetables and is therefore a major problem for growers in horticulture and viniculture. Unfortunately, it is scarcely affected by natural or synthetic protective compounds, as it uses minute protein pumps (so-called ABC transporters) to pump these back out again.
When the fungus comes into contact with toxic substances, these initially enter it unhindered. About 15 minutes later, an emergency mechanism starts up and the fungus secretes the toxic substances so that their concentration in the fungus falls below the lethal dose.
Schoonbeek studied the genes involved in the secretion of toxic substances by ABC transporters. He discovered that the activity of the pumps was partly controlled by the toxic substances. Upon entering the fungus, these stimulate the fungal DNA to produce certain proteins, which then immediately pump these substances out of the fungus.
The researcher established that this mechanism in B. cinerea is comparable to multiple drug resistance in humans. Multiple drug resistance is when cells that have been treated with one type of medicine, become resistant to a completely unrelated group of medicines. Transport proteins also play an important role in multiple drug resistance.
One of these ABC transporters is the protein BcatrB. This protein is involved in defending the fungus against many different toxic substances. For example, it is active against resveratrol, a plant defence compound from grapevines. Therefore the fungus can easily break through the defence lines of grape plants. Although antibiotic-producing bacteria are used to protect plants successfully against other pathogens, the phenazine antibiotics they contain cannot stop B. cinerea. This is because they also activate the production of the BcatrB protein and are therefore immediately pumped back out again. This new information is helpful in developing new strategies to control grey mould diseases.
The research was funded by the Netherlands Organisation for Scientific Research.
NWO (Netherlands Organization for Scientific Research)
Schoonbeek studied the genes involved in the secretion of toxic substances by ABC transporters. He discovered that the activity of the pumps was partly controlled by the toxic substances. Upon entering the fungus, these stimulate the fungal DNA to produce certain proteins, which then immediately pump these substances out of the fungus.
The researcher established that this mechanism in B. cinerea is comparable to multiple drug resistance in humans. Multiple drug resistance is when cells that have been treated with one type of medicine, become resistant to a completely unrelated group of medicines. Transport proteins also play an important role in multiple drug resistance.
One of these ABC transporters is the protein BcatrB. This protein is involved in defending the fungus against many different toxic substances. For example, it is active against resveratrol, a plant defence compound from grapevines. Therefore the fungus can easily break through the defence lines of grape plants. Although antibiotic-producing bacteria are used to protect plants successfully against other pathogens, the phenazine antibiotics they contain cannot stop B. cinerea. This is because they also activate the production of the BcatrB protein and are therefore immediately pumped back out again. This new information is helpful in developing new strategies to control grey mould diseases.
The research was funded by the Netherlands Organisation for Scientific Research.
NWO (Netherlands Organization for Scientific Research)
Drug Resistance Current Events and Drug Resistance News RSSTaking aim at mysterious DNA structures in the battle against cancer
Designers of anti-cancer drugs are aiming their arrows at mysterious chunks of the genetic material DNA that may play a key role in preventing the growth and spread of cancer cells, according to an article in the current issue of Chemical & Engineering News, ACS' weekly newsmagazine.
There's a speed limit to the pace of evolution, Penn biologists say
Researchers at the University of Pennsylvania have developed a theoretical model that informs the understanding of evolution and determines how quickly an organism will evolve using a catalogue of "evolutionary speed limits."
Ineffective monotherapies common in high-burden malarious countries
ACTwatch, a research project led by PSI, in collaboration with the London School of Hygiene and Tropical Medicine, released evidence today that indicates that artemisinin combination therapy, the most effective medicines for treating malaria, continue to have a significantly low presence on the market among populations considered to be most at risk.
Paradigm shift needed to combat drug resistance
When people travel, bacteria and other infectious agents travel with them. As about a billion people cross international borders each year, many more billions of the bugs come along for the ride.
UM School of Medicine researchers find extreme genetic variability in malaria parasite
Researchers at the University of Maryland School of Medicine Center for Vaccine Development (CVD) have charted the extreme genetic differences that occur over time in the most dangerous malaria parasite in the world.
Scientists join forces to explain HIV spread in Central and East Africa
Scientists studying biology and geography may seem worlds apart, but together they have answered a question that has defied explanation about the spread of the HIV-1 epidemic in Africa.
Pancreatic cancer: Researchers find drug that reverses resistance to chemotherapy
For the first time researchers have shown that by inhibiting the action of an enzyme called TAK-1, it is possible to make pancreatic cancer cells sensitive to chemotherapy, opening the way for the development of a new drug to treat the disease.
MUHC/McGill researchers to WHO: Time to revise tuberculosis treatment guidelines
Tuberculosis is a global threat that affects more than 10 million people each year. Working with colleagues in the United States and France, Dr. Dick Menzies of the Research Institute of the McGill University Health Centre (RI-MUHC) has placed current tuberculosis treatment guidelines under the microscope in a new study.
Man-made crises 'outrunning our ability to deal with them,' scientists warn
The world faces a compounding series of crises driven by human activity, which existing governments and institutions are increasingly powerless to cope with, a group of eminent environmental scientists and economists has warned.
New research strategy for understanding drug resistance in leukemia
UCSF researchers have developed a new approach to identify specific genes that influence how cancer cells respond to drugs and how they become resistant. This strategy, which involves producing diverse genetic mutations that result in leukemia and associating specific mutations with treatment outcomes, will enable researchers to better understand how drug resistance occurs in leukemia and other cancers, and has important long-term implications for the development of more effective therapies.
More Drug Resistance Current Events and Drug Resistance News Articles
 |
Cancer Drug Resistance (Cancer Drug Discovery and Development) by Beverly A. Teicher (Editor) Leading experts summarize and synthesize the latest discoveries concerning the changes that occur in tumor cells as they develop resistance to anticancer drugs, and suggest new approaches to preventing and overcoming it. The authors review physiological resistance based upon tumor architecture, cellular resistance based on drug transport, epigenetic changes that neutralize or bypass drug cytotoxicity, and genetic changes that alter drug target molecules by decreasing or eliminating drug binding and efficacy. Highlights include new insights into resistance to antiangiogenic therapies, oncogenes and tumor suppressor genes in therapeutic resistance, cancer stem cells, and the development of more effective therapies. There are also new findings on tumor immune escape mechanisms, gene... |
 |
Antimicrobial Drug Resistance: Mechanisms of Drug Resistance, Volume 1 (Infectious Disease) by Douglas L. Mayers (Editor) The volumes included in Antimicrobial Drug Resistance represent the first comprehensive, multidisciplinary reference covering the area of antimicrobial drug resistance in bacteria, fungi, viruses, and parasites from basic science, clinical, and epidemiological perspectives. The first volume, Antimicrobial Drug Resistance, Mechanisms of Drug Resistance, is dedicated to the biological basis of drug resistance and effective avenues for drug development. With the emergence of more drug-resistant strains, the approach to dealing with the drug resistance problem must include the research of different aspects of the mechanisms of bacterial resistance and the dissemination of resistance genes as well as research utilizing new genomic information. These approaches will permit the design... |
 |
Revenge Of The Microbes: How Bacterial Resistance Is Undermining The Antibiotic Miracle by Abigail A. Salyers (Author), Dixie D. Whitt (Author) 'What is antibiotic resistance, and why should I be concerned with it?' Media coverage and political and scientific discussions about 'superbugs' that defy our current treatments, genetically-modified foods in our fields and grocery stores, the threat of bioterrorism, and the use of antibiotics in agriculture have increased citizen awareness and fears regarding the issues surrounding antibiotic resistance. "Revenge of the Microbes: How Bacterial Resistance Is Undermining the Antibiotic Miracle" is a single source of answers to this and other questions average people are asking. Written by experts with extensive experience in the field, "Revenge of the Microbes" provides the scientific information readers will need to form opinions and make informed decisions regarding the use of... |
 |
Science Magazine July 18 2008 Drug Resistance by Science Magazine |
 |
Drug Abuse Resistance Education Awareness Ribbon Mouse Pad by MyHeritageWear.com The Drug Abuse Resistance Education proudly displayed on a mouse pad. There is no better way to achieve awareness for the meaning of the Drug Abuse Resistance Education than to display it on your mouse pad for everyone to see. The mouse pad measures at 9.25 x 7.75, it is machine washable, and the colors will not fade or run. Start gaining awareness today by presenting your Drug Abuse Resistance Education mouse pad at work or at home. It is certain to keep your mouse rolling in style all while gaining support and awareness! |
 |
Dead or Alive: Final Starring: Shô Aikawa, Maria Chen, Richard Chen, Jason Chu, Josie Ho Directed By: Takashi Miike Also With: Ken Takeuchi (Producer), Makoto Okada (Producer), Mitsuru Kurosawa (Producer), Toshiki Kimura (Producer), Hitoshi Ishikawa (Writer), Ichiro Ryu (Writer), Yoshinobu Kamo (Writer) The ace cop of a totalitarian police force and a drifting android play their parts in a post-apocalyptic society. They are destined to fight. Their encounter will change them forever. Studio: Kino International Release Date: 10/05/2004 Run time: 88 minutes |
 |
Antibiotic Resistance: Stopping the Superbugs Directed By: ITV Also With: ITV (Producer) |
 |
PILL CONTAINER - First Aid - MEDICAL ALERT - Key Chain with Water Resistance - Large Size / Color BLACK by Changsheng Hardware |
 |
The Killers Within: The Deadly Rise of Drug-Resistant Bacteria by Michael Shnayerson (Author), Mark J. Plotkin (Author) A battle is taking place on the frontiers of medicine between rapidly evolving bacteria that threaten our health and the doctors who are struggling to outwit them. These bacteria are everywhere: in and on our bodies, in homes, schools, hospitals, crowded airplaines, day-care centers. And, as THE KILLERS WITHIN makes frighteningly clear, so far the bacteria are winning. |
 |
Drug Resistance in Cancer Cells by Kapil Mehta (Editor), Zahid H. Siddik (Editor), Susan E. Bates (Editor) The inability of cancer drugs to destroy metastatic tumors is the major reason why cancer therapy fails. Even though the process of drug design has become exceedingly sophisticated in recent years, there is not a single drug available that is 100% effective against metastatic cancer. Resistance to treatment with anticancer drugs results from a variety of factors including individual variations in patients and somatic/genetic differences in tumors, even those from tissue of origin. Although it is a generally accepted fact that the majority of cancers arise from a single precursor cell, it is naïve to consider that tumor is a collection of genetically identical cells. Genetic instability and accumulation of mutations are important hallmarks of cancer cells. This means that dividing... |
| © 2009 BrightSurf.com |