Strange, underworld microbes raise hopes for alien life
Oct. 19, 2006
Researchers have found what they say are isolated bacterial colonies flourishing deeper in the Earth’s crust than was known to be possible.
The strange beings thrive on radioactive water, in a harsh setting cut off from surface life and its dependence on sun energy, the scientists claim. That, they add, raises hopes that other planets in our solar system could also harbor hardy microbes within them.
Lisa Pratt of Indiana University Bloomington (left) and Tullis Onstott of Princeton University in Princeton, N.J. collect microbes in the Lupin gold mine in Nunavut Territory, Canada. (Credit: Lisa Pratt).
“These bacteria are truly unique in the purest sense of the word,” said Li-Hung Lin of National Taiwan University in Taipei, lead author of a paper on the find in the Oct. 20 issue of the research journal Science.
The microbes were reported to come from 2.8 km (almost two miles) underground at a gold mine site.
Most creatures in the known food web depend on sunlight one way or another. They either live off it directly, like plants, or they eat those that do.
Some organisms live so far underground or below the sea, though, that they seem to live apart from this network, independent of sunlight.
But proof that these are totally isolated from surface food webs has been lacking, the researchers said. And for many of these creatures, it has been unclear whether they were recent arrivals bound for extinction or permanent residents.
That could change with the new find, they said.
“We know surprisingly little about the origin, evolution and limits for life on Earth,” said biogeochemist Lisa Pratt of Indiana University Bloomington, a member of the research team.
“Scientists are just beginning to study the diverse organisms living in the deepest parts of the ocean. The rocky crust on Earth is virtually unexplored at depths more than half a kilometer below the surface. The organisms we describe in this paper live in a completely different world than the one we know.”
The researchers argued that the bacterial communities they found are permanent, apparently millions of years old, and depend on radiation from uranium ores rather than sunlight. This raises the possibility that similar bacteria could live beneath the surfaces of worlds such as Mars or Jupiter’s moon Europa, the scientists said.
The finding came after they learned of a newly cracked rock seeping water in a gold mine near Johannesburg, South Africa, and saw a chance to study deep rock untouched by man. They descended hot, gas-choked mineshafts to investigate.
Genetic analyses revealed multitudes of bacterial species, the researchers found, dominated by one type related to bacteria from the division Firmicutes. Other Firmicutes are familiar to scientists from deep-sea springs called hydrothermal vents. The studies suggested the underground Firmicutes lost contact with their surface cousins between 3 million and 25 million years ago, the researchers added.
“We know how isolated the bacteria have been because our analyses show that the water they live in is very old and hasn’t been diluted by surface water,” among other reasons, Lin said.
The microbes use hydrogen for respiration, an energy-generating chemical process, the researchers added. The hydrogen is available thanks to radioactive decay of the elements uranium, thorium, and potassium, they said, which emit radiation as they decay. The radiation breaks down water, releasing its component hydrogen.
Hydrogen gas contains pent-up energy that can be released in the presence of certain other substances such as oxygen or sulfate—as the 1937 Hindenburg disaster demonstrated. Firmicutes can harvest energy from the reaction of hydrogen and sulfate, the researchers found, and the bacteria’s chemical waste products serve as food for other, neighboring microbes.
Indirectly, the firmicutes capture radiation energy and pass the benefits along to everyone else, Lin and colleagues argued—much as organisms that thrive on sunlight, such as trees and plankton, do in our surface habitat.
Here Comes Spider-Goat?
Genetically Altered Goats May Lead to Strong Silk-like Threads
Jan. 31— It may be impossible to craft a silk purse from a sow’s ear. But one day, it may be possible to fashion a silk bulletproof vest from, of all things, goat’s milk.
For decades, scientists have been in awe of the lowly spider and the magical material it uses to spin its web. After all, strands of spider silk are a mere one-tenth the thickness of human hair, yet they can snag a bee traveling 20 miles per hour without breaking.
Ounce for ounce, spider silk is five times stronger than steel and about three times tougher than man-made fibers such as Kevlar. And that makes the material ideal for all sorts of interesting uses — from better, lighter bulletproof vests to safer suspension bridges.
But “harvesting” spider silk hasn’t been easy. Unlike silkworms, spiders aren’t easy to domesticate. “Spiders are territorial carnivores, they eat each other if placed in contact or in close proximity,” says Jeffrey Turner, president and CEO of Nexia Biotechnoloies, Inc. “It’s like trying to farm tigers.”
Now, researchers at the Quebec-based Nexia along with scientists at the U.S. Army’s Soldier Biological Chemical Command (SBCCOM) in Natick, Mass., say they may have figured a way out of the sticky situation.
In the latest issue of Science, the researchers report that they’ve managed to successfully create artificial spider silk that’s nearly as good as the real thing — and without involving a single spider.
How? Turner and his team of bio scientists took the genes responsible for creating spider silk into the cells of mammals, such as goats. Using those genes, the re-engineered goats were then able to produce in their milk the same protein that makes up spider’s silk.
Turner says that by isolating those proteins from the goats’ milk, they were then able to “spin” a thread remarkably similar to natural spider silk.
“On things like toughness and modulus of elasticity — the ability to stretch without breaking — we’re right on the money,” says Turner.
Not Quite There Yet
Still, Turner does note there are still many other factors that need to be worked out before we see bridges built with man-made silk.
For one, the amount of silk-building protein that Nexia has been able to produce has been limited to a few strands. And it isn’t clear yet how much protein may be able to be harvested in such a manner. Turner says his team expects to have a second research paper that would examine such details out by the end of this year.
And Nexia’s experimental silk strands aren’t an exact match — yet. Turner notes that they’re only 20 percent to 40 percent as strong as natural spider silk.
“We still have more work to do,” says Turner. “But to get this far is just a step forward.”
Herd of Silky Goats?
And moving even further forward is what really excites Turner and his military partners.
The most promising aspect of their research so far: The spider genes are faithfully passed on among the experimental goats. And that means producing more artificial silk might be as simple as breeding more of the genetically-enhanced goats naturally.
Since starting the experiment three years ago, Turner says Nexia’s flock in Montreal has grown to nearly 50 goats. Within the next several years he expects the flock to scale up to “several thousand.”
And as the company continues its research and grows out the herd, Turner believes that it won’t be long before we could see commercial applications. Nexia has already plans to market the material, dubbed BioSteel, for use as fine suture material and biodegradable fishing line by 2003 or 2004.
If all goes well by then, he says it wouldn’t be too much of a stretch to see lightweight body armor made of artificial spider silk within three to five more years.
Microwave weapon intensified by sweaty skin
The Pentagon’s “less-lethal” microwave-based crowd-control weapon – the Active Denial System (ADS) – produces potentially harmful hotspots when used in built-up areas, and its effects can be intensified by sweaty skin, tests have revealed. The flaws call into question the weapon’s usefulness in hot conditions, like those in Iraq.
The ADS fires a microwave beam intended to heat skin without causing damage, while inflicting enough pain to force the victim to move away. However, tests of the weapon showed that reflections off buildings, water or even the ground can produce peak energy densities twice as high as the main beam. Contact with sweat or moist fabric such as a sweaty waistband further intensifies the effect.
The safety concerns, revealed in the details of 14 tests carried out by the US air force between 2002 and 2006, were acquired under a Freedom of Information request by Edward Hammond of the Sunshine Project USA, which campaigns against the use of biological and non-lethal weapons.
Test details released to the organisation last year revealed that volunteers taking part in the tests had been banned from wearing glasses or contact lenses because of safety fears.
Active Denial Systems under development include small, portable versions and vehicle and aircraft-mounted systems. The new tests ranged from simple experiments to determine pain thresholds to large-scale war games involving hundreds of subjects. Some tests involved finding whether alcohol increased subjects’ ability to withstand the beam and how trained dogs responded, to determine the effect of accidental exposure on dog handling teams.
Nevertheless, the weapon may be safer than some alternatives. More than 9000 experimental exposures to the ADS have produced just six cases of blistering and one second-degree burn caused by an accidental overexposure. The US army wants permission to deploy the system in Iraq, but the decision has been delayed while tests continue.
The secretary of the US Air Force, Michael Wynne, said recently that new non-lethal weapons like the microwave ADS should be used on Americans before being deployed to places like Iraq.
“If we’re not willing to use it here against our fellow citizens, then we should not be willing to use it in a wartime situation,” he told CNN.
Hammond hopes these comments may stimulate debate on the use of the ADS and other non-lethal weapons. “I think that you would see a strongly negative public reaction and quite possibly an increase in violence if US police were to use the ADS in riot control,” he told New Scientist. “I’m sad to say that such an outpouring of concern would probably be considerably more muted if the weapon was deployed in Iraq first.”
Eyeball squeezing could correct sight
09:19 21 March 02
A light tap on the side of your head could one day restore your eyesight, believe scientists. The tap would tighten a band of artificial muscle wrapped round your eyeballs, changing their shape and bringing blurry images into focus. While the idea has a high ‘yuk’ factor, the people behind it are confident it will be a safe and effective way to improve vision.
How artificial muscles put the squeeze on poor sight
Mohsen Shahinpoor and his team at the University of New Mexico call their artificial muscle a “smart eye band”. It will be stitched to the sclera, the tough white outer part of the eyeball, and activated by an electromagnet in a hearing-aid-sized unit fitted behind one ear.
Most of the eye’s focusing is done by the cornea, the hard transparent surface that covers both the pupil and the iris; the lens is responsible only for fine-tuning. Light travels through the cornea and lens to focus on the retina at the back of the eyeball. The closer an object is, the farther back in the eye it will be focused. The lens compensates by adjusting its strength to bring the focus back onto the retina.
If the cornea or lens do not focus strongly enough or the eyeball is too short, the light will focus behind the retina, blurring images of close-up objects. This is long-sightedness. Conversely, if the eyeball is too long, the light will focus in front of the retina, yielding the blurry images of far-off objects characteristic of short-sightedness.
Tightening the smart eye band causes the eyeball to elongate, just as squeezing the middle of a peeled hard-boiled egg causes the egg to lengthen. In long-sighted people this pushes the retina backwards, bringing close-up objects back into focus.
Expanding the eye band causes the eyeball to shorten. In short-sighted people this will bring the retina forward to intersect with the focused light, making far-off images sharp and clear again.
Stitching a band of artificial muscle to your eyeball sounds drastic, but Shahinpoor says the necessary surgical techniques are already commonly used for treating detached retinas. He claims his smart eye band is far more flexible than laser surgery, in which a laser flattens the cornea by eroding part of it. Laser surgery can only correct short-sightedness.
With the smart eye band implanted, you’d set your eyes to read a book, say, by clicking a button on the device sitting behind your ear. This would generate a magnetic field to activate the eye band’s artificial muscle.
The artificial muscle comprises a series of “bi-strips” (see graphic), each made up of two lengths of a biocompatible polymer containing lithium ions, surrounded by a coil of thin gold wire. At the end of each bi-strip is an electrode.
Switching on the magnetic field induces a pulse of current in the coil, which in turn builds up a small charge on the electrodes. The positively charged lithium ions in the polymer are attracted to the negative electrode, causing the whole bi-strip to bunch up and tighten the band around the eyeball. So the eye’s focal length becomes electronically controllable.
Though Shahinpoor’s idea is still on the drawing board, Jim Schwiegerling of the Optical Sciences Center at the University of Arizona says the technology could be of enormous benefit to older people who have lost the ability to change focus from distant to near objects.
“When you sit down to read a book, you could just switch it on, and when you are done reading, you could turn it off and go out and drive a car,” he says. Shahinpoor will present the design for his bionic eye at an optical technology conference in San Diego, California later in March.
Bottled Water Flim-Flam
January 2, 2004
The $7.7 billion market for bottled water in the United States is fueled by the belief that it is safer and healthier than tap water. A recent study by the Natural Resources Defense Council (NRDC) demonstrates that frequently the opposite is true.
After testing more than 1000 bottles of water from 103 different companies, the NRDC uncovered microbial content in excess of state guidelines in one-third of the brands it sampled. The NRDC also discovered synthetic organic chemicals in one-fifth of its samples, usually at levels below state and federal limits. While tap water is not exempt from contamination, EPA guidelines do call for near constant testing of tap water quality. Bottling facilities are required to test less frequently and if they find pathogens like E. coli or fecal coliform they can still sell their water with a small disclaimer on the label.
While tap water is subject to extensive regulation and testing by the EPA, the agency does not oversee the bottled water industry. That task falls to the Food and Drug Administration, but only if the water crosses state lines. The FDA has adopted only some of the EPA’s water standards and has the equivalent of less than one full-time staff person dedicated to developing and issuing bottled water rules. The 60 to 70 percent of bottled water brands that are produced and sold within one state are subject solely to state regulations and only 7 states effectively monitor bottled water.
The plastic used to package the 6 billion gallons of bottled water sold in the U.S. in 2002 amounts to 1.5 million tons of plastic. Once produced, plastic water bottles clog landfills and litter the landscape, and toxins in the plastic can find their way into ground water. Nine out of 10 plastic water bottles end up as garbage or litter. That’s 30 million discarded bottles a day.
Extracting the quantities of water necessary to fill that many bottles has sizeable environmental repercussions. In Mecosta County, Michigan, for example, Ice Mountain, a subsidiary of Nestle Waters North America, pumps more than a half million gallons of water per day from local springs. For the right to drain central Michigan’s waters, Ice Mountain paid a $100 licensing fee and garnered millions of dollars in tax credits from the state. Residents of Mecosta County have organized a boycott of Ice Mountain and Michigan Citizens for Water Conservation has taken the company to court, arguing that the massive pumping enterprise does not constitute a “reasonable use” of the state’s water.
Flatulent Cows to Fuel Oil Sands?
Fri Apr 2, 7:47 AM ET
TORONTO (Reuters) – A Calgary brokerage touted new ways to fuel northern Alberta’s massive oil sands developments on Thursday in an April 1 research report promising power from flatulent cows.
The hoax report, done up to look like a genuine research document, said a company called Bovine Hydrocarbon Collection, based in Picture Butte, Alberta, would collect the methane from gassy cows in special TurboSucks tanks made of old scuba gear, vacuum cleaners and surplus airplane parts.
“FirstEnergy has examined the technology as closely as possible, and believes it has significant potential,” the report said.
The author of the report, Steven Paget, was not immediately available for comment.
A Web search for bovine hydrocarbon collection shows a series of scientific documents, none of which have anything to do with methane, oil sands or the rocket-like TurboSucks gadget pictured in the FirstEnergy report
Spinach protein implant could restore sight
14:36 01 October 01
A team of scientists hopes to improve the sight of blind people by implanting proteins from spinach leaves into their eyes. When light falls on the proteins, it creates an electrical voltage, which could stimulate healthy regions of the retina and produce meaningful images, they say.
“The idea is to insert these proteins into cells in the retina,” says Elias Greenbaum of Oak Ridge National Laboratory in Tennessee, US. “If we can do that, we know light can make them produce voltages high enough to stimulate the optic nerve.”
Greenbaum, who is working on the project with Mark Humayun of the University of Southern California’s Doheny Eye Institute, Los Angeles, says the spinach proteins – known as photo-reaction centres – perform a similar task to photoreceptor cells in the retina. These cells, which lie at the base of the retina, send electrical pulses to the optic nerve when illuminated. These impulses are then interpreted as images by the brain. Humayun has already shown that artificially stimulating retinal cells with electrical voltages can produce very elementary vision. “He found that if you lay an electrode array over retinal tissue and stimulate it, you can produce basic images that the person can recognise,” says Greenbaum.
The two now hope to use the photo-reaction centres to replace damaged or diseased photoreceptor cells in blind or partially-sighted people.
“In two of the major diseases that cause blindness, you lose the photoreceptor cells,” says Greenbaum. To do it, they plan to embed the photo-reaction centres into tiny fatty spheres called liposomes and inject these into the membranes of retinal cells.
When light falls on them, Greenbaum hopes they will produce voltages strong enough to trigger electrical impulses down the optic nerve. “What we need to do is find out whether these voltages can trigger neural events and allow the brain to interpret the images,” says Greenbaum.
Greenbaum and Humayun are currently experimenting with implanting the proteins into retinal cells in the laboratory and stress it will be some time before they try the technique in animals or humans.