Clipmarks | Silkweaver's 'biochemistry' clips

Transformers - The Nature of Alien Life

Sat, 23 Aug 2008 12:52:47 GMT

clipped by: Silkweaver
clipper's remarks: The driving factor is a pragmatic desire to improve mental capacity. Alien beings may have already reached a point in their evolution where, having exhausted the potential of their biological brains, they have taken the next logical step and opted for robotic brains equipped with artificial intelligence. This brain swap may not be as far off for humans as one might think. In only a few decades, the computer revolution here on Earth has produced supercomputers capable of performing more than a quadrillion calculations per second.

According to research by Hans Moravec, an artificial-intelligence expert at Carnegie Mellon University, that rate trumps the human brain’s estimated top speed of 100 trillion calculations per second. Some scientists speculate that in a few decades, an event called the technological singularity will occur, and machines armed with computer brains will become sentient and surpass human intelligence. Civilizations equipped with technology light-years ahead

Clip Source: kemo-d7.livejournal.com

The existence of a race of sentient alien robots might be
not just possible, but inevitable.

Daniel C. Dennett points out that we do not consider chemicals to be alive. Even self-replicating crystals and clever nanobots are not "living"; we consider them to be completely mechanical. Yet we are made of these non-living, "mechanical" chemicals. Not only are we made of robots, and we still consider ourselves to be valid conscious life, but the evolution of all life is from such mindless robots.

As life is based in biology, and biology in biochemistry, chemistry is based on the cold, non-living laws of physics.

Given the current pace of development, it is easy to imagine artificial life venturing out into the universe and leaving us fragile humans behind.

In fact, we might be living in a "post-biological universe" right now, in which intelligent extraterrestrials somewhere have exchanged organic brains for artificial ones.

Tags: ai, science fiction, alien life

Breakthrough in Solar Energy: Scientists mimic plants' energy storage system

Thu, 31 Jul 2008 22:58:24 GMT

clipped by: Silkweaver
clipper's remarks: 'GIANT LEAP' FOR CLEAN ENERGY

Sunlight has the greatest potential of any power source to solve the world's energy problems, said Nocera. In one hour, enough sunlight strikes the Earth to provide the entire planet's energy needs for one year.

James Barber, a leader in the study of photosynthesis who was not involved in this research, called the discovery by Nocera and Kanan a "giant leap" toward generating clean, carbon-free energy on a massive scale.

"This is a major discovery with enormous implications for the future prosperity of humankind," said Barber, the Ernst Chain Professor of Biochemistry at Imperial College London. "The importance of their discovery cannot be overstated since it opens up the door for developing new technologies for energy production thus reducing our dependence for fossil fuels and addressing the global climate change problem."

Clip Source: www.physorg.com

In a revolutionary leap that could transform solar power from a marginal, boutique alternative into a mainstream energy source, MIT researchers have overcome a major barrier to large-scale solar power: storing energy for use when the sun doesn't shine.

Until now, solar power has been a daytime-only energy source, because storing extra solar energy for later use is prohibitively expensive and grossly inefficient. With today's announcement, MIT researchers have hit upon a simple, inexpensive, highly efficient process for storing solar energy.

Requiring nothing but abundant, non-toxic natural materials, this discovery could unlock the most potent, carbon-free energy source of all: the sun.

Inspired by the photosynthesis performed by plants

have developed an unprecedented process that will allow the sun's energy to be used to split water into hydrogen and oxygen gases.

may be recombined inside a fuel cell, creating carbon-free electricity to power your house or your electric car, day or night

Tags: energy, solar energy, photosynthesis

Enzymes made to order

Sun, 06 Jul 2008 01:18:43 GMT

clipped by: Silkweaver
clipper's remarks: Making enzymes is a tricky business. Even the names of the techniques sound mind-boggling, with the process involving a mix of 'quantum mechanical computation', 'advanced protein engineering' and 'directed evolution'.

while naturally occurring enzymes speed reaction rates by many billion (or even trillion) fold, the synthetic enzymes gave more conservative boosts – around 100,000 fold.

"The acceleration [achieved] is really rather modest by comparison to Nature," admits Houk – but it's still incredibly exciting

Clip Source: www.cosmosmagazine.com

In a world first, scientists have managed to synthesise entirely new functional enzymes that could pave the way to reactions not seen in the natural world.

As far as proteins go, enzymes are darn hard workers. They play a key role in almost all chemical reactions occurring in nature, from cell division and replication to digestion

Acting as 'catalysts', their job is to assist otherwise lethargic reactions occur at much faster, biologically useful speeds

Scientists have been able to modify existing enzymes for use in everything from baking bread and brewing beer, to the development of novel cleaning products

For the first time, we have been able to computationally design [and create] enzymes from scratch

These enzymes are capable of dealing with substances for which no naturally occurring enzymes have evolved

in principle, the technique could be used to produce enzymes capable of "accelerating any desired reaction at all"

Tags: biochemistry, synthetic enzymes

Some like it hot! Structure of receptor for hot chili pepper and pain revealed

Tue, 20 May 2008 10:44:47 GMT

clipped by: Silkweaver

Clip Source: www.physorg.com

You can now not only feel the spicy kick of a jalapeno pepper, you can also see it in full 3D, thanks to researchers at Baylor College of Medicine in Houston.

Using sophisticated equipment, the research team led by Dr Theodore G. Wensel, professor of biochemistry and molecular biology at BCM, generated the first three dimensional view of the protein that allows you to sense the heat of a hot pepper.

The report appears in the current issue of the Proceedings of the National Academy of Sciences.

“This protein, known as TRPV1, not only senses spicy foods, but also makes it possible to feel real heat and the pain and inflammation related to other medical conditions,”

The outside stimulus used in this study was the heat of a chili pepper. It has been known for years that the burning sensation results from the action of a chemical known as capsaicin on TRPV1 found on the nerve cell membrane.

“Any time you feel a burn or pain sensation, it is mediated by a TRPV1 channel.

Tags: neuroscience, molecular biology

Epigenetic research uncovers new targets for modification enzymes

Mon, 28 Apr 2008 00:17:25 GMT

clipped by: Silkweaver

Clip Source: www.physorg.com

Enzymes regulating genetic expression can be just as important as the genome itself, increasing evidence shows. The expanding field of epigenetics focuses on the multiple influences on DNA and surrounding molecules that determine whether genes are turned on or off during development and disease processes.

"This discovery broadens our view of methyltransferases and tells us that epigenetic regulation in cells is even more complicated than we thought," says principal investigator Xiaodong Cheng, PhD, professor of biochemistry at Emory University School of Medicine and a Georgia Research Alliance Eminent Scholar.

We have known for some time that we had a great deal more to discover about methyltransferases. This is an important piece of the puzzle, and additional research will continue to help us unwind the multiple mechanisms involved in epigenetic gene regulation."

Tags: biology, genetics, epigenetics, molecular biology

Fear can be cured, soon; somewhat disquieting.

Mon, 23 Jul 2007 18:02:15 GMT

clipped by: Silkweaver
clipper's remarks: One little (or not so little) concern regarding these wonderful news, is that the same mechanism can be selectively used to implant fears not only to cure them, an hardly resistible temptation for those hungry for power & control.

Clip Source: pressesc.com

MIT finds cure for fear

MIT biochemists have identified a molecular mechanism behind fear, and successfully cured it in mice, according to an article in the journal Nature Neuroscience.

Inhibiting a kinase, an enzyme that change proteins, called Cdk5 facilitates the extinction of fear learned in a particular context,

Conversely, the learned fear persisted when the kinase's activity was increased in the hippocampus, the brain's center for storing memories, the scientists found.

"Remarkably, inhibiting Cdk5 facilitated extinction of learned fear in mice," Tsai said. "This data points to a promising therapeutic avenue to treat emotional disorders and raises hope for patients suffering from post-traumatic stress disorder or phobia.

Tags: neuroscience, biochemistry, psychology

Mouse finding Violates Laws of Heredity

Fri, 05 Jan 2007 03:17:35 GMT

clipped by: Silkweaver
clipper's remarks: The mouse says: Still a long way to go to fully understand heredity

Clip Source: www.sciam.com

Mouse Finding Violates Laws of Heredity

DNA has long been considered the sole arbiter of heredity. New research seems to show, however, that its lesser known cousin, RNA--previously thought only to facilitate the creation of proteins as dictated by the genetic code--may itself pass traits down through the generations.

Fifty years ago, researchers observed that the factors controlling the amount of purple coloring in certain corn kernels deviated from the accepted laws of genetics. Genetic variants that should have been bred out could sometimes exert their empurpling effect in subsequent generations. Dubbed paramutation, the phenomenon remained unexplained.

In experiments with mutant mice, Minoo Rassoulzadegan of Inserm in France and his colleagues observed a similar phenomenon. A mutation in the Kit gene is known to produce white patches of fur on the toes and tails of brown mice. The researchers bred together mice that each carried one normal copy of the gene and one aberrant copy--that is, they were heterozygous. Mice that inherit two normal copies of the gene should not exhibit this coloring. But oddly enough, the team found that a large percentage of the resulting mice in their study that inherited only normal copies of the gene from their heterozygous parents did in fact have the white spots.

The exact mechanism by which RNA transmits the spotting trait to progeny in the absence of the gene that causes spotting in the parent remains mysterious. But the finding does challenge the existing understanding of genetics, and it may have implications for humans. In a commentary accompanying the report, Paul Soloway of Cornell University remarks: "A particularly intriguing possibility is that such RNAs regulate other non-genetic modes of inheritance, such as metabolic or behavioral imprinting." The research and commentary appear in today's Nature.

Tags: science, biology, genetics, biochemistry

A new way of gene control discovered

Thu, 28 Dec 2006 00:36:13 GMT

clipped by: Silkweaver
clipper's remarks: Another step in understanding the complex mechanism of transcription and development

Clip Source: www.physorg.com

Peering deep within the cells of fruit flies, developmental biologists at the Kimmel Cancer Center at Thomas Jefferson University in Philadelphia may have discovered a new way that genes are turned on and off during development.

If they're right, and the same processes are at work in higher organisms, including mammals, the findings could eventually have implications for improving the understanding of a range of diseases, including childhood cancer.

Reporting in the journal Cell, Alexander Mazo, Ph.D., professor of biochemistry and molecular biology at Jefferson Medical College, Svetlana Petruk, Ph.D., and their co-authors focused on pieces of genetic material called non-coding (nc)RNAs. About two-thirds of the human genome is converted into such RNAs (the better known messenger RNAs are translated into proteins), though the function of the majority is unknown. The researchers detailed a possible mechanism by which ncRNAs briefly control the functioning of homeotic, or HOX, genes, which guide the master developmental plan of the organism.

According to Dr. Mazo, the researchers found that one of the likely mechanisms behind ncRNAs' ability to regulate essential coding genes is through a "transcription interference" mechanism. "Such mechanisms are known in bacteria and yeast, but not much is known in higher organisms," he explains.

"Importantly, non-coding RNAs are very tightly developmentally regulated, as we show in case of bxd RNAs," Dr. Mazo notes. "These create an enormous potential to regulate the neighboring coding genes in a time- and tissue-specific manner. This is a new type of transcriptional regulation mechanism for higher eukaryotes, and it is very likely that it is conserved in mammals."

Tags: biology, biochemistry, genetics, development, cancer

Organ regeneration - what can we learn from the newt

Thu, 14 Dec 2006 13:09:34 GMT

clipped by: Silkweaver

Clip Source: www.betterhumans.com

If the accidentally regenerative MRL mice are anything to go by, there is the strong possibility that salamander-style regeneration of limbs and organs could be brought to mammals - and humans in particular. The biochemistry might just be there, latent and unused ... after all, we all grew the limbs and organs we have once already.

When a newt loses a limb, the limb regrows. What is more, a newt can also completely repair damage to its heart. Scientists at the Max Planck Institute for Heart and Lung Research in Bad Nauheim have now started to decode the cellular mechanisms in this impressive ability to regenerate and have discovered the remarkable plasticity of newt heart cells.

whereas humans cannot regenerate damaged heart muscle adequately after a heart attack and the destroyed muscle tissue scars over instead, following damage, a newt’s heart can be completely repaired and the organ’s function can be completely restored.

The key to this ability to regenerate are the heart muscle cells themselves. When a newt’s heart sustains damage, its cells can lose their characteristic properties; they can dedifferentiate. The researchers were able to show that proteins typical of heart muscle cells - the heavy myosin chain and various troponins - were dramatically down-regulated in this process. At the same time, the cells embark on massive cell division to build up new heart muscle. It takes around two weeks for the heart function to be restored in the newt. The data shows that at this point the expression of the muscle-specific proteins is again normal, i.e. the cells have differentiated again, and have regained their characteristic properties.

Tags: science, medicine, regenrative medicine, biology