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Nature press release for 13 June issue

June 13, 2002

[1] LIFELINES: VANCOMYCIN RESISTANCE GENES FOUND (pp746-750)

Genes specific to antibiotic-resistant Enterococcus faecalis - a scourge of hospitals worldwide - are huddled together on the same spot of its genome and could point to new targets for drugs to combat E. faecalis infections, according to this week`s Nature.
Enterococcus faecalis is an essential part of our natural gut flora but can easily infect wounds. It is the third most common cause of hospital-acquired infection and the appearance of drug-resistant strains of the bacterium in the 1980s made it even more of a problem.
Michael Gilmore and colleagues at the University of Oklahoma Health Sciences Center, Oklahoma City, compared a strain of E. faecalis that can withstand even the last-resort antibiotic vancomycin with E. faecalis from the gut. They found that the genes that make the bacterium virulent are clustered together in a `pathenogenicity island`. Such genetic regions have been identified in other bacteria but never before in the Enterococcus group.
CONTACT:
Michael S. Gilmore tel +1 405 271 1083, e-mail michael-gilmore@ouhsc.edu

[2] SPACE: BREAKING NEWS (pp720-722; N&V)

An impressive piece of astronomical detective work has resulted in the first-ever discovery of a recent asteroid collision. David Nesvorny and colleagues of the Southwest Research Institute, Boulder, Colarado, have identified a group of 39 known asteroids as debris from a collision that took place 5.8 million years ago. Two of the fragments are large, 14 and 19 km in diameter, and there seems to have been little dynamical or collisional evolution since this big bang.
This collection of bodies of varying size, all the same age, should provide the answers to many mysteries of the asteroid belt - including the nature of 'space weathering' and the incidence of planetesimal collisions.
"The cluster is young enough that many erosional and weathering processes thought to occur on asteroid surfaces may not have had time to erase the tell-tale signatures of the break-up event", says Derek Richardson of the University of Maryland at College Park, in an accompanying News and Views article.
CONTACT:
David Nesvorny tel +1 303 546 0023, e-mail davidn@boulder.swri.edu
Derek Richardson tel +1 301 405 8786, e-mail dcr@astro.umd.edu

[3] TECHNOLOGY: TWO SINGLE MOLECULE TRANSISTORS(pp722-725 and 725-729; N&V)

Two papers in this week's Nature demonstrate the potential of molecules as electronic components in nanometre-scale devices. Both make transistors from purpose-designed molecules containing transition-metal atoms.
Daniel C. Ralph of Cornell University, Ithaca, New York, and colleagues use a single cobalt atom, and Hongkun Park of Harvard University, Cambridge, Massachusetts, and colleagues use a pair of vanadium atoms in the other. Both demonstrate transistor operation based on a tunable flow of electrons through the metal atom.
"Right now, these single-molecule or single-atom transistors are no competition for silicon transistors," say Silvano De Franceschi and Leo Kouwenhoven of the ERATO Mesoscopic Correlations Project, Delft University of Technology, in an accompanying News and Views article. "But they will serve for studying electron motion through nanoscale objects, and for the development integrated electronic devices built on single molecules".
CONTACT:
Daniel C. Ralph tel +1 607 255 9644, e-mail ralph@ccmr.cornell.edu
Hongkun Park tel +1 617 496 0815, e-mail hpark@chemistry.harvard.edu
Leo Kouwenhoven tel +31 15 278 6064, e-mail leo@qt.tn.tudelft.nl

[4] ECOLOGY: LOSS OF APATITE (pp729-731)

Analyses of strontium isotopes and strontium/calcium ratios in soil, water and trees of the Hubbard Brook Experimental Forest, a 3,160-hectare reserve in the White Mountain National Forest in New Hampshire, have revealed a previously unknown calcium pool in the soil.
Mycorrhizal fungi associated with the root systems of some trees can extract calcium directly from the mineral apatite (calcium phosphate), report Joel D. Blum, of the University of Michigan, Ann Arbor, and colleagues in this week`s Nature. This route bypasses the soil cation exchange thought to supply all of the bioavailable calcium.
These findings suggest that cation loss from forests subjected to acid deposition may not be as severe as previously thought, and so might not be restricting recovery of these forests.
CONTACT:
Joel D. Blum tel +1 734 615 3242, e-mail jdblum@umich.edu

[5] LIFELINES: RED BLOOD CELL DEVELOPMENT PROTEIN (pp758-763; N&V)

Mitchell J. Weiss and colleagues of the Children`s Hospital in Philadelphia, report in this week`s Nature that a substance called alpha haemoglobin stabilizing protein (AHSP) is required for normal red blood cell development. They suggest that the protein may malfunction in blood diseases characterized by an excess of a-haemoglobin, such as b-thalassaemia. Delivering AHSP, or molecules like it, could therefore be a way to treat such diseases.
In an accompanying News and Views article, Lucio Luzzatto and Rosario Notaro of the National Institute for Cancer Research, Genoa, Italy, discuss the background and implications of this work.
CONTACT:
Mitchell J. Weiss tel +1 215 590 0565, e-mail weissmi@email.chop.edu
Lucio Luzzatto tel +39 010 352 776, e-mail luzzatto@hp380.ist.unige.it

[6] PHYSICS: HOW TO BUILD A QUANTUM COMPUTER (pp709-711)

Memory in quantum computers is created by the manipulation of quantum bits. In classical computers, memory is a string of ones and zeros; quantum bits (qubits) can be in a superposition of many different states at once, so a quantum computer has the potential to be much more powerful than a classical computer.
The only physical system for which all the ingredients necessary for quantum computing have been demonstrated in the laboratory is ion trap technology, but it has not been clear whether the ion trap system is scalable in practice.
In this week`s Nature, D. Kielpinski of Massachusetts Institute of Technology, Cambridge, and colleagues propose an architecture for a large-scale quantum computer based on an array of interconnected ion traps that overcomes some of the existing obstacles and makes computing with large numbers of qubits a realistic goal.
CONTACT
D. Kielpinski tel +1 617 452 3180, e-mail Utonium@mit.edu

[7] LIFELINES: ATHEROSCLEROSIS INITIATOR (pp750-754; N&V)

Although the accumulation of cholesterol in artery walls is a hallmark of atherosclerosis, the mechanisms initiating the deposition of this lipid have been poorly understood.
In this week`s Nature, Jan Boren of Göteborg University, Sweden, and colleagues show that a highly specific interaction between vascular proteoglycans and apoB100 - the major protein constituent of atherogenic cholesterol-containing lipoproteins - has an important role in initiating atherosclerosis.
"The data presented are another important step in achieving the ambitious goal of understanding atherogenesis, and may provide a novel approach to the prevention of cardiovascular diseases," says Bart Staels of the Institut Pasteur de Lille and the Université de Lille II, France, in an accompanying News and Views article.
CONTACT:
Jan Boren tel +46 31 3422949, e-mail jan.boren@wlab.wall.gu.se
Bart Staels tel +33 3 20 87 73 88, e-mail Bart.Staels@pasteur-lille.fr

[8] ECOLOGY: BEES GIVE COFFEE CROPS A BUZZ (p708)

Bees - unexpectedly - are good for coffee. Coffee (Coffea arabica) is self-pollinating, and so the insects were thought to make little difference to the plant. But in a Brief Communication to this week`s Nature, David Roubik of the Smithsonian Tropical Research Institute in Panama, shows that bees can increase coffee yields by over 50%.
Roubik looked at coffee plants in Panama visited predominantly by settled immigrant African honeybees. Different pollinating insects have different effects on bush yield.
Coffee yields in some places, such as Kenya and Indonesia, have fallen during the past half-century, perhaps because more intensive farming has destroyed habitat for potential pollinators. The new finding shows the importance of managing agricultural landscapes to include pollinators and other beneficial wild species.
CONTACT:
David Roubik tel +507 212 8109, e-mail Roubikd@tivoli.si.edu

[9] AND FINALLY: MIRROR IMAGES PREVENT SELF POLLINATION (p707)

Whether the sex organs of some plants hang to the left, or the right, is controlled by their genes. The different orientations may have evolved to improve reproduction, researchers report in a Brief Communication to this week`s Nature.
In several different groups of plants, members of the same species can have the style (female sex organ) pointing either to the left or the right, resulting in flowers that are mirror images of each other. Documented more than a century ago, enantiostyly (as it is known) was thought to be a random phenomenon.
Now Linley Jesson and Spencer Barrett of the University of Toronto, Canada, find that enantiostyly is inherited through a single gene. Also they show that the mechanism could have evolved to ensure that the plants breed with others, not themselves. Bees pick up pollen on one side of their body in enantistylous plants, and cannot deposit it on the style of other flowers of that same plant. On flowers that swing the other way however, pollen rubs off in exactly the right place.
CONTACT
Spencer Barrett tel +1 416 978 4151, e-mail Barrett@botany.utoronto.ca

ALSO IN THIS ISSUE

[10]        Density-dependent mortality and the latitudinal gradient in species diversity (pp732-735; N&V)

[11]        Geographic structure and dynamics of coevolutionary selection (pp735-738)

[12]        Spike train dynamics predicts theta-related phase precession in hippocampal pyramidal cells (pp738-741)

[13]        Role of experience and oscillations in transforming a rate code into a temporal code (pp741-746)

[14]        T-box gene tbx5 is essential for formation of the pectoral limb bud (pp754-758)

[15]        Regulation of Arabidopsis cryptochrome 2 by blue-light-dependent phosphorylation (pp763-767)

GEOGRAPHICAL LISTING OF AUTHORS

The following list of places refers to the whereabouts of authors on the papers numbered in
this release. The listing may be for an author`s main affiliation, or for a place where they are
working temporarily. Please see the PDF of the paper for full details.

CANADA
Ontario
Toronto: 9

PANAMA
Balboa: 8

SWEDEN
Göteborg: 7

UNITED KINGDOM
Leicester: 15

UNITED STATES OF AMERICA
California
        Berkeley: 3
        Los Angeles: 15
        San Francisco: 7
        Santa Cruz: 11
Colorado
        Boulder: 2, 6
Connecticut
        New Haven: 4
Massachusetts
        Cambridge: 3, 6, 13
Michigan
        Ann Arbor: 4, 6
Minnesota
        St. Paul: 10
North Carolina
        Durham:10
New Hampshire
        Durham: 4
New Jersey
        Newark: 12
        Princeton: 14
New York State
        Ithaca: 3, 4
        Millbrook: 4
        Syracuse: 4
Oklahoma        
        Oklahoma City: 1
Pennsylvania
        Philadelphia: 5
Tennessee
        Knoxville: 10
Washington State
        Pullman: 11

Nature Publishing Group Reference