Scientists sequence the bovine genome
CHAMPAIGN, Ill., April 23 (UPI) -- A U.S.-led international consortium of scientists says it has sequenced the bovine genome, showing the genetic features that separate cattle from humans.
The six-year effort has produced the first full genome sequence of any ruminant species, officials said, consisting of at least 22,000-protein coding genes and more similar to that of humans than to the genomes of mice or rats.
University of Illinois Professor Harris Lewin said the cattle genome appears to have been significantly reorganized since its lineage diverged from those of other mammals.
"Among the mammals, cattle have one of the more highly rearranged genomes," Lewin said. "They seem to have more translocations and inversions (of chromosome fragments) than other mammals, such as cats and even pigs, which are closely related to cattle."
The sequence of the cow's 29 pairs of chromosomes and its X chromosome -- the Y chromosome was not studied -- provides new insights into bovine evolution and the unique traits that make cattle useful to humans, Lewin said.
The research -- coordinated by Richard Gibbs and George Weinstock of the Baylor College of Medicine, Chris Elsik of Georgetown University and Ross Tellam of the Commonwealth Scientific and Industrial Research Organization of Australia -- is featured in the journal Science.
Plants absorb more carbon under hazy skies
LONDON, April 23 (UPI) -- British scientists say they've found plants absorb carbon dioxide more efficiently under Earth's polluted skies than they would in cleaner settings.
"Surprisingly, the effects of atmospheric pollution seem to have enhanced global plant productivity by as much as a quarter from 1960 to 1999," said lead author Lina Mercado of the Center for Ecology & Hydrology. "This resulted in a net 10 percent increase in the amount of carbon stored by the land once other effects were taken into account."
The scientists said an increase in microscopic particles released by human activities, and subsequent changes in cloud cover, caused a decline in the amount of sunlight reaching Earth's surface from the 1950s up to the 1980s.
Although less sunlight reduces photosynthesis, the atmospheric particles scatter light so a plant's surface receives light from multiple directions rather than straight from the sun. The researchers said plants are then able to convert more available sunlight into growth because fewer leaves are in the shade.
"Although many people believe well-watered plants grow best on a bright sunny day, the reverse is true," said study co-author Stephen Sitch of Britain's Meteorological Office Hadley Center. "Plants often thrive in hazy conditions such as those that exist during periods of increased atmospheric pollution."
The study, which included University of Exeter Professor Peter Cox, appears in the journal Nature.
Phase 1 malaria vaccine trial to begin
ROCKVILLE, Md., April 23 (UPI) -- A U.S. biotechnology company says it will conduct the first clinical trial involving humans of a malaria vaccine that contains the whole malaria parasite.
Sanaria Inc. of Rockville, Md., said it is using a weakened form of the whole malaria parasite that's been harvested from irradiated mosquitoes. Other malaria vaccine candidates use only small portions of the parasite.
Sanaria said its vaccine will be assessed in 104 healthy volunteers beginning next month.
Myron Levine, director of the University of Maryland School of Medicine's Center for Vaccine Development said the Sanaria vaccine is based, in part, on findings from parallel studies conducted during the early 1970s by teams at the Center for Vaccine Development and the Naval Medical Research Center. Levine said those findings were never translated into a vaccine development effort because the task was considered to be impossible.
Anti-malaria parasite chemical developed
LEEDS, England, April 23 (UPI) -- British scientists say they have created chemical compounds that kill the most deadly malaria parasites, including those resistant to existing drugs.
The University of Leeds researchers said the compounds work by preventing the enzyme dihydroorotate dehydrogenase, which is essential to the growth of the parasite Plasmodium falciparum, from working.
"Without this enzyme, Plasmodium falciparum is unable to grow and therefore it dies," said lead researcher Glenn McConkey. "The inhibitors developed at Leeds bind to the … enzyme in the parasite and stop it functioning, preventing the proliferation of the parasites, which live in red blood cells. In addition, our chemicals are equally effective against parasites that have developed resistance to drugs."
Since the enzyme is not an essential one in humans, the compounds have no major side-effects to the human host.
"Our chemicals are particularly exciting as they kill malaria parasites at low concentrations, something that is important for medicines as they are massively diluted on entering the bloodstream and, unlike many pharmaceutical products, we have a firm understanding of the molecular basis of their action," McConkey said. "This project highlights the benefits of combining biological and chemistry disciplines."
The research appears in the Journal of Medicinal Chemistry.
