Featured Research

from universities, journals, and other organizations

Scientists Discover New Stage In Malarial Infection

Date:
December 14, 2000
Source:
Washington University School Of Medicine
Summary:
Researchers have identified a previously unknown step that enables the malaria parasite to spread in the bloodstream. And they have found a way to block this key event. The findings, reported in the Dec. 12 online edition of Proceedings of the National Academy of Sciences, may lead to promising targets for drug development.

St. Louis, Dec. 11, 2000 -- Researchers have identified a previously unknown step that enables the malaria parasite to spread in the bloodstream. And they have found a way to block this key event. The findings, reported in the Dec. 12 online edition of Proceedings of the National Academy of Sciences, may lead to promising targets for drug development.

Malaria afflicts 300 to 500 million people worldwide and kills nearly 2 million children each year. The parasites that cause the disease multiply inside red blood cells, bursting from them to invade new cells.

"But little was known about how the parasites break out of cells," said Daniel E. Goldberg, M.D., Ph.D., senior author of the paper and a professor of medicine and of molecular microbiology in the Howard Hughes Medical Institute at Washington University School of Medicine in St. Louis. "Now that we have identified the major stages, we will be able to study the process better."

As if they were instantly replaying a football scrimmage, the researchers slowed the action with inhibitors. They discovered that the parasites emerge from red blood cells in two steps. "First, they exit enclosed in a sac they have made. Then the sac quickly bursts, releasing the parasites," Goldberg said.

Enzymes that break down proteins—proteases—were thought to help the parasite emerge from red blood cells. And inhibitors of these enzymes are effective against other infectious agents, notably the virus that causes AIDS. Therefore, Goldberg's group studied the effect of a protease inhibitor called E64 on the malaria parasite.

E64 did not stop the parasites from escaping out of red blood cells. But it prevented them from rupturing the sac that enclosed them. When E64 was removed, the parasites spilled from the sac to infect other red blood cells. Similar sacs had been seen in infected blood samples, but only fleetingly, and their significance had not been grasped. "By better understanding the role of proteases in the parasite's escape from the host cell, we may be able to develop clinically useful inhibitors that will keep it from getting out to infect new cells," Goldberg said.

###

Salmon BL, Oksman A, Goldberg DE. Malaria parasite exit from the host erythrocyte: a two step process requiring extraerythrocytic proteolysis. Proceedings of the National Academy of Sciences, online edition, Dec. 12, 2000.

The work was supported by the Burroughs Wellcome Fund


Story Source:

The above story is based on materials provided by Washington University School Of Medicine. Note: Materials may be edited for content and length.


Cite This Page:

Washington University School Of Medicine. "Scientists Discover New Stage In Malarial Infection." ScienceDaily. ScienceDaily, 14 December 2000. <www.sciencedaily.com/releases/2000/12/001214082638.htm>.
Washington University School Of Medicine. (2000, December 14). Scientists Discover New Stage In Malarial Infection. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2000/12/001214082638.htm
Washington University School Of Medicine. "Scientists Discover New Stage In Malarial Infection." ScienceDaily. www.sciencedaily.com/releases/2000/12/001214082638.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