Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Malaria parasite zeroes in on molecule to enhance its survival

23.02.2009
A team of researchers from Princeton University and the Drexel University College of Medicine has found that the parasite that causes malaria breaks down an important amino acid in its quest to adapt and thrive within the human body. By depleting this substance called arginine, the parasite may trigger a more critical and deadlier phase of the disease.

The scientists believe that shedding light on this poorly understood aspect of malaria metabolism has given them new insights on the interactions between the parasite and its human hosts. The work also may point the way to better treatments.

"The more we know about the parasite's metabolic network, the more intelligent we can be about targeting therapies that will cure malaria," said Kellen Olszewski, a graduate student at Princeton University and first author of the Feb. 18 Cell Host & Microbe paper describing the work. The project was led by Manuel Llinás, an assistant professor of molecular biology and the Lewis-Sigler Institute for Integrative Genomics at Princeton.

As a central part of the research, the scientists created a "metabolomic" profile of the parasite, Plasmodium falciparum. Metabolomics is a new field that aims to analyze metabolic processes by simultaneously measuring the levels of all of the more than 500 core metabolites that make up an organism's "metabolic network." A metabolite is a chemical involved in metabolism, the process by which an organism takes up nutrients from the environment and converts them to energy and the molecular building blocks that cells use to grow. Amino acids, sugars, nucleotides and vitamins are all metabolites.

To conduct the study, the team used a mass spectrometry-based method developed in the neighboring laboratory of Joshua Rabinowitz, an assistant professor of chemistry at Princeton and another author on the paper. Mass spectrometry is a highly sensitive technique that identifies chemicals based on their size and electrical charge.

The researchers were interested in seeing how the concentrations of metabolites in parasite-infected human red blood cells change over a single 48-hour "generation" of parasite growth. Scanning the data, the scientists noted that arginine levels dramatically dipped by the end of one 48-hour cycle.

"The parasite destroys this amino acid specifically and preferentially over all other amino acids," Olszewski said.

Follow-up experiments showed that the parasite doesn't break down arginine in order to grow, suggesting that this process serves some secondary function that helps P. falciparum proliferate within the human body. Arginine is an essential fuel for the human body's immune system, which uses it to produce a molecule called nitric oxide that is highly toxic to foreign organisms. The parasite-led attack on arginine may be an attempt by the parasite to "switch off" a human immune function that might threaten its survival, the researchers said.

Scientists are interested in studying the metabolism of P. falciparum to understand how organisms adapt to a parasitic lifestyle. Understanding this is important because many of the drugs used to treat malaria successfully in the past have targeted some aspect of the parasite's metabolism.

"Designing the next generation of anti-malarial drugs will likely require a detailed knowledge of the 'weak points' in the parasite's metabolic network," Llinás said.

According to the World Health Organization, some 350 to 500 million people are infected with malaria every year by mosquitos carrying one of the four human malaria parasites, P. falciparum, P. vivax, P. malariae or P. ovale. The P. falciparum infections are by far the most deadly, killing more than 1 million people each year, mainly young children and pregnant women. The disease, which can incapacitate a victim for several weeks, also imposes a massive social and economic burden. People living in endemic areas can be infected up to several times a year. About 60 percent of the cases of malaria worldwide and more than 80 percent of malaria deaths occur in sub-Saharan Africa.

Other authors on the paper include: Daniel Wilinski, a research specialist in the Llinás lab; and Joanne Morrisey, James Burns and Akhil Vaidya, all of the Center for Molecular Parasitology at the Drexel University College of Medicine.

The research was supported by the Burroughs Wellcome Fund; the National Institutes of Health; the National Science Foundation; and the Arnold and Mabel Beckman Foundation.

Kitta MacPherson | EurekAlert!
Further information:
http://www.princeton.edu

More articles from Life Sciences:

nachricht Transport of molecular motors into cilia
28.03.2017 | Aarhus University

nachricht Asian dust providing key nutrients for California's giant sequoias
28.03.2017 | University of California - Riverside

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Transport of molecular motors into cilia

28.03.2017 | Life Sciences

A novel hybrid UAV that may change the way people operate drones

28.03.2017 | Information Technology

NASA spacecraft investigate clues in radiation belts

28.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>