13-year-old's science fair project finds fungus in the environment
Researchers have pinpointed the environmental source of fungal infections that have been sickening HIV/AIDS patients in Southern California for decades. It literally grows on trees.
This false-color electron microscope image catches the fungus Cryptococcus gattii in the act of producing its infectious spores. The club-shaped blue structure is a reproductive organ called the basidium, which projects off the fungus body like an apple off a tree. The spores are colored yellow, and are like seeds that can give rise to a new organism.
Credit: Center for Microbial Pathogenesis, Duke University
The discovery is based on the science project of a 13-year-old girl, who spent the summer gathering soil and tree samples from areas around Los Angeles hardest hit by infections of the fungus named Cryptococcus gattii (CRIP-to-cock-us GAT-ee-eye).
Cryptococcus, which encompasses a number of species including C. gattii, causes life-threatening infections of the lungs and brain and is responsible for one third of all AIDS-related deaths.
The study, which appears Aug. 21 in PLOS Pathogens, found strong genetic evidence that three tree species -- Canary Island pine, Pohutukawa and American sweetgum -- can serve as environmental hosts and sources of these human infections.
"Just as people who travel to South America are told to be careful about drinking the water, people who visit other areas like California, the Pacific Northwest and Oregon need to be aware that they are at risk for developing a fungal infection, especially if their immune system is compromised," said Deborah J. Springer, Ph.D., lead study author and postdoctoral fellow in the Center for Microbial Pathogenesis at Duke University School of Medicine.
A few years ago, Duke's chairman of Molecular Genetics and Microbiology, Joseph Heitman M.D., was contacted by longtime collaborator and UCLA infectious disease specialist Scott Filler, M.D., whose daughter Elan was looking for a project to work on during her summer break. They decided it would be fun to send her out in search of fungi living in the greater Los Angeles area.
The student sampled 109 swabs of more than 30 tree species and 58 soil samples, grew and isolated the Cryptococcus fungus, and then sent those specimens to Springer at Duke. Springer DNA-sequenced the samples from California and compared the sequences to those obtained from HIV/AIDS patients with C. gattii infections.
She was surprised to find that specimens from three of the tree species were genetically almost indistinguishable from the patient specimens.
The researchers also found that the C. gattii isolated from the environment were fertile, reproducing either by sexual or asexual reproduction.
"That finding is important for long-term prevalence in the environment, because this fungal pathogen will be able to grow, reproduce, disperse spores, and serve as a source of ongoing infections," Springer said.
"Cryptococcus gattii VGIII isolates causing infections in HIV/AIDS patients in Southern California: Identification of the local environmental source as arboreal," Deborah J. Springer, R. Blake Billmyre, Elan E. Filler, Kerstin Voelz, Rhiannon Pursal, Piotr Mieczkowski, Robert A. Larsen, Fred S. Dietrich, Robin C. Mary, Scott G. Filler, and Joseph Heitman. PLOS Pathogens, August. 21, 2014.
Karl Bates | Eurek Alert!
New Technique Maps Elusive Chemical Markers on Proteins
03.07.2015 | Salk Institute for Biological Studies
New approach to targeted cancer therapy
03.07.2015 | CECAD - Cluster of Excellence at the University of Cologne
Wind turbines could be installed under some of the biggest bridges on the road network to produce electricity. So it is confirmed by calculations carried out by a European researchers team, that have taken a viaduct in the Canary Islands as a reference. This concept could be applied in heavily built-up territories or natural areas with new constructions limitations.
The Juncal Viaduct, in Gran Canaria, has served as a reference for Spanish and British researchers to verify that the wind blowing between the pillars on this...
New technique combines electron microscopy and synchrotron X-rays to track chemical reactions under real operating conditions
A new technique pioneered at the U.S. Department of Energy's Brookhaven National Laboratory reveals atomic-scale changes during catalytic reactions in real...
Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and a half billion years ago.
Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and...
A team of scientists including PhD student Friedrich Schuler from the Laboratory of MEMS Applications at the Department of Microsystems Engineering (IMTEK) of...
The three-year clinical trial results of the retinal implant popularly known as the "bionic eye," have proven the long-term efficacy, safety and reliability of...
25.06.2015 | Event News
16.06.2015 | Event News
11.06.2015 | Event News
03.07.2015 | Press release
03.07.2015 | Agricultural and Forestry Science
03.07.2015 | Health and Medicine