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 What happens in the cell nucleus after fertilization
06.12.2016 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Researchers uncover protein-based “cancer signature”
05.12.2016 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Simple processing technique could cut cost of organic PV and wearable electronics

06.12.2016 | Materials Sciences

3-D printed kidney phantoms aid nuclear medicine dosing calibration

06.12.2016 | Medical Engineering

Robot on demand: Mobile machining of aircraft components with high precision

06.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>