Featured Research

from universities, journals, and other organizations

Gene That Regulates Mold's Resistance To Drugs Identified

Date:
November 20, 2008
Source:
Montana State University
Summary:
Researchers have found a gene that regulates mold's resistance to anti-mold drugs.

The growth of fungus is compared with and without oxygen. Normoxia, on the left, refers to the presence of oxygen. Hypoxia is the absence. The top and bottom rows show two normal strains of fungus. A mutant strain, in the center row, does not grow without oxygen, while the normal strains do.
Credit: Photo courtesy of Robert Cramer

Montana State University scientists concerned about lethal mold infections have found a gene that regulates the mold's resistance to drugs.

The gene, called srbA, allows molds to thrive during infections even when inflammation reduces its oxygen supply, said Robert Cramer, senior author of a paper published in the Nov. 7 issue of PLoS Pathogens. When the gene is removed, the mold becomes much more vulnerable to lack of oxygen and can no longer grow to cause disease.

The gene is found in humans and molds, but the researchers studied it in a common mold called Aspergillus fumigatus, said Cramer, assistant professor of fungal pathogenesis in MSU's Department of Veterinary Molecular Biology. A. fumigatus can invade the lungs and cause dangerous diseases, including Invasive Pulmonary Aspergillosis. Patients with a compromised immune system, especially organ transplant patients, are particularly at risk.

"The incidence of potentially lethal infections caused by normally benign molds has increased tremendously over the last two decades," the researchers wrote.

The scientists discovered the value of srbA after creating a mutant version of the fungus without the gene, Cramer said. Tests showed that the loss of srbA affected 87 genes in the fungus. Without the gene, the mutant could no longer grow when oxygen was limited, which occurs during mold infections. The mutant mold without srbA could no longer cause disease. It was also highly susceptible to antifungal drugs, more vulnerable than the original, complete mold.

Further study showed that srbA plays a critical role in the making of ergosterol, the fungal-form of cholesterol, Cramer said. The gene in humans is associated with the making of cholesterol. Ergosterol and cholesterol are necessary components of cell membranes.

"The reason we're interested is because ergosterol is a target for most of the antifungal drugs that are available," Cramer said. "These drugs target the synthesis of ergosterol. ... If you get rid of ergosterol, you kill the mold."

Sven Willger, a postdoctoral researcher in Cramer's lab and first author of the PLoS Pathogens paper, said the absence of srbA changed the way the mold cells grew. Instead of growing from the tip, they branched off from several other locations. The confusion became apparent under a transmission electron microscope.

The researchers said in their paper that they demonstrated for the first time that it is significant that invasive molds adapt to reduced oxygen levels during infection.

Besides Cramer and Willger, MSU co-authors of the paper are Srisombat Puttikamonkul and Nora Grahl, both graduate students in Cramer's lab; and James Burritt, assistant professor of microbiology. Co-authors from other institutions are Kwang-Hyung Kim and Christopher Lawrence from the Virginia Bioinformatics Institute, and Laurel Metzler, Robert Barbuch and Martin Bard from Indiana University-Purdue University.


Story Source:

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


Cite This Page:

Montana State University. "Gene That Regulates Mold's Resistance To Drugs Identified." ScienceDaily. ScienceDaily, 20 November 2008. <www.sciencedaily.com/releases/2008/11/081107143855.htm>.
Montana State University. (2008, November 20). Gene That Regulates Mold's Resistance To Drugs Identified. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2008/11/081107143855.htm
Montana State University. "Gene That Regulates Mold's Resistance To Drugs Identified." ScienceDaily. www.sciencedaily.com/releases/2008/11/081107143855.htm (accessed October 22, 2014).

Share This



More Plants & Animals News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Cadaver Dogs Aid Search for More Victims of Suspected Indiana Serial Killer

Cadaver Dogs Aid Search for More Victims of Suspected Indiana Serial Killer

Reuters - US Online Video (Oct. 21, 2014) Police in Gary, Indiana are using cadaver dogs to search for more victims after a suspected serial killer confessed to killing at least seven women. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
White Lion Cubs Unveiled to the Public

White Lion Cubs Unveiled to the Public

Reuters - Light News Video Online (Oct. 21, 2014) Visitors to Belgrade zoo meet a pair of three-week-old lion cubs for the first time. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
'Cadaver Dog' Sniffs out Human Remains

'Cadaver Dog' Sniffs out Human Remains

AP (Oct. 21, 2014) Where's a body buried? Buster's nose can often tell you. He's a cadaver dog, specially trained to find human remains and increasingly being used by law enforcement and accepted in courts. These dogs are helping solve even decades-old mysteries. (Oct. 21) Video provided by AP
Powered by NewsLook.com
White Lion Cubs Born in Belgrade Zoo

White Lion Cubs Born in Belgrade Zoo

AFP (Oct. 20, 2014) Two white lion cubs, an extremely rare subspecies of the African lion, were recently born at Belgrade Zoo. They are being bottle fed by zoo keepers after they were rejected by their mother after birth. Duration: 00:42 Video provided by AFP
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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