Genes and brain centers that regulate meal size in flies identified

May 21, 2010 By Leave a Comment

Washington, May 21 (ANI): Scientists from the California Institute of Technology (Caltech) and Yale University have identified two genes that appear to regulate meal sizes and frequency in fruit flies.

Both genes, the leucokinin neuropeptide and the leucokinin receptor, have mammalian counterparts that seem to play a similar role in food intake, indicating that the steps that control meal size and meal frequency are not just behaviorally similar but are controlled by the same genes throughout the animal kingdom.

In animals, food intake is regulated to keep body weight constant over a long period of time. Most animals consume food in discrete bouts-that is, in meals.

“Identifying the genes and molecules that regulate meal-related parameters is essential for understanding the relationships between body weight and caloric intake,” says Bader Al-Anzi, a research scientist at Caltech and the lead author of the Current Biology study.

Al-Anzi and his colleagues developed an assay to examine feeding behavior in the common fruit fly, Drosophila melanogaster. In this assay, genetically normal flies were starved for one day and then transferred into a vial containing sugar meal mixed with red food dye. Invariably, the flies became satiated during their exposure to red food, and their small abdomens turned red. Next, the researchers performed the same experiment using mutant fly strains.

“Our hope was that if flies contained mutations in genes involved in meal regulation, those flies would eat excessive amounts of red food, making them visibly bloated with red abdomens,” says Al-Anzi,

Two mutant fly strains produced notable results. One strain contained a mutation in the gene encoding the leucokinin neuropeptide (a peptide initially identified for its ability to induce insect gut contraction), and the second strain contained mutated versions of the receptor that binds to leucokinin. In the assay, both types of fly mutants ate to such excess that they became visibly bloated, with their crops-food storage organs-stretched to the limit with red-dyed food.

Surprisingly, Al-Anzi says, “although in the short term these flies tend to overeat, in the long run they consume a similar amount of food as normal flies. This was largely due to the fact that they are compensating for the large increase in meal size by reducing the number of times they eat.” Whereas mutant flies consumed four or five large meals in a single day, normal flies ate seven or eight small meals.

In additional experiments, Al-Anzi and his colleagues found that although the leucokinin neuropeptide is found exclusively in the brain, the leucokinin receptor is found in neurons located in both the brain and the foregut-an area of the gut that contains stretch receptors known to be responsible for monitoring meal size in other insects.

The researchers also found that introducing a normal copy of the leucokinin neuropeptide or of the leucokinin receptor gene to these neurons in their corresponding mutant flies fully restored normal feeding behavior.

Furthermore, when these same neurons were destroyed in normal, nonmutant flies, the flies began to consume abnormally large meals, just like mutants.

“This proves that we identified the right genes responsible for the flies”” bingeing as well as the fly brain center that regulates meal size and frequency,” Al-Anzi says.

The study will appear in the June 8 issue of the journal Current Biology. (ANI)

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“Ancient city of ”modern” galaxies” discovered

May 12, 2010 By Leave a Comment

Washington, May 12 (ANI): Astronomers led by Texas A&M scientists have identified what may be called the “ancient city of ”modern” galaxies”.

The group of roughly 60 galaxies, called CLG J02182-05102, is nearly 10 billion years old, and possibly the earliest, most distant cluster of galaxies ever detected.

However, it”s not the size nor the age of the cluster that amazes the team of researchers led by Dr. Casey Papovich, an assistant professor in the Texas A&M Department of Physics and Astronomy and member of the George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy.

Rather, it”s the surprisingly modern appearance of CLG J02182-05102 that has them baffled – a huge, red collection of galaxies typical of only present-day galaxies.

Papovich said: “It”s like we dug an archaeological site in Rome and found pieces of modern Rome amongst the ruins.”

While its neighbouring galaxies appear vastly smaller and far fainter, Papovich says CLG J02182-05102 stands out as a densely populated bundle of ancient galaxies.

Enormous red galaxies at the centre contain almost 10 times as many stars as our Milky Way, he notes, combining for a total size that rivals that of the most monstrous galaxies of our nearby universe.

Before now, Papovich says, such a finding would be considered by many astronomers to be highly unlikely, considering the time frame in which they were found.

Papovich said: “The predictions are that these things should be very rare when the universe was 4 billion years old, and yet, we found them.

“Not only did we find them, it looks for all intents and purposes like they had already formed completely and evolved into the large concentrations of galaxies that we see in clusters today.”

Exactly why these particular galaxies are fully formed that early is what Papovich and his collaborators – which include astronomers from NASA”s Jet Propulsion Laboratory at the California Institute of Technology (Caltech) as well as Carnegie Observatories – hope to one day uncover, but for now, studying CLG J02182-05102 could help them and other researchers better understand how galaxies form and cluster in general.

The study will appear in Astrophysical Journal. (ANI)

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When it comes to adoption, US parents avoid African-American babies, boys

April 21, 2010 By Leave a Comment

Washington, Apr 21 (ANI): Parents pursuing adoption within the United States tend to avoid taking African-American babies and boys, according to a study.

The above results came from the study conducted by economists from the California Institute of Technology (Caltech), the London School of Economics, and New York University (NYU).

They found that parents have strong preferences regarding the types of babies they will apply for, tending to choose non-African-American girls, and favouring babies who are close to being born as opposed to those who have already been born or who are early in gestation.

These preferences are significant, and can be quantified in terms of the amount of money the potential adoptive parents are willing to pay in finalizing their adoption.

While the data are intriguing, the real value of the study is that it can give policymakers a more rational, evidence-driven base from which to consider the implications of policies and laws, such as those that restrict adoption by single-sex and foreign couples, said the researchers.

The key to these findings, according to the researchers, was the data set they were able to put together.

“These data are unique,” said Leeat Yariv, associate professor of economics at Caltech.

The researchers, however, were able to gather information—from a website run by an adoption intermediary—over a five-year period (between 2004 and 2009).

The intermediary works to bring together—to match—potential adoptive parents with birth mothers seeking to relinquish their children for adoption.

The website operates somewhat like an online real estate site. We could see the attributes of the children—race, gender, age—and even the finalization costs, or the amount of money the adoptive parent would need to pay to finalize the adoption. In addition, we could see which children the potential adoptive parents applied for,” she explained.

In other words, the team could see which babies attracted interest from potential adoptive parents, and determine which traits were most likely to lead to a successful adoption.

This revealed three main patterns—first, the researchers found that a non-African-American baby is seven times more likely to “attract the interest and attention of potential adoptive parents than an African-American baby,” said Felli.

The second pattern shown was the gender preference.

“A girl has a higher—by slightly more than one-third—chance of attracting the attention of potential adoptive parents than a boy,” said an author of the study.

The researchers also found that the interest of potential adoptive parents in a particular baby depends on the stage of gestation.

“While unborn children become increasingly attractive over the birth mother”s pregnancy, probably because the match involves less uncertainty from the adoptive parents” perspective,” said another study author.

“We find that the desirability of a child decreases dramatically right after birth,” added the author.

This means, according to researchers that “bureaucratic obstacles disrupting an adoption plan at the time of birth are extremely detrimental to the future prospects of the child.” (ANI)

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Scientists unravel chemistry of Titan’s hazy atmosphere

September 17, 2009 By Leave a Comment

Washington, September 16 (ANI): In a new research, a team of scientists has unraveled the chemical evolution of the orange-brownish colored atmosphere of Saturn’s moon Titan, the only solar system body besides Venus and Earth with a solid surface and thick atmosphere.

Scientists at University of Hawai’i at Manoa carried out the research.

The UH Manoa team, including Xibin Gu and Seol Kim, conducted simulation experiments mimicking the chemical reactions in Titan’s atmosphere utilizing crossed molecular beams in which the consequence of a single collision between molecules can be followed.

The team’s experiments indicate that triacetylene can be formed by a single collision of a “radical” ethynyl molecule and a diacetylene molecule.

An ethynyl radical is produced in Titan’s atmosphere by the photodissociation of acetylene by ultraviolet light.

Photodissociation is a process in which a chemical compound is broken down by photons.

“Surprisingly, the photochemical models show inconsistent mechanisms for the production of polyynes,” said Kaiser, who is the principal investigator of this study.

The mechanism involved in the formation of triacetylene, was also confirmed by accompanying theoretical calculations by Alexander Mebel, a theoretical chemist at Florida International University.

These theoretical computations also provide the 3D distribution of electrons in atoms and thus the overall energy level of a molecule.

To apply these findings to the real atmosphere of Titan, Danie Liang and Yuk Yung, planetary scientists at Taiwan’s Academia Sinica and California Institute of Technology (Caltech), respectively, performed photochemical modeling studies of Titan’s atmosphere.

All data together suggest that triacetylene may serve as a building block to form more complex and longer polyynes and produce potential precursors for the aerosol-based layers of haze surrounding Titan.

The study demonstrated for the first time that a sensible combination of laboratory simulation experiments with theory and modeling studies can shed light on decade old unsolved problems crucial to understand the origin and chemical evolution of the solar system.

The researchers hope to unravel next the mystery of the missing ethane lakes on Titan – postulated to exist for half a century, but not detected conclusively within the framework of the Cassini-Huygens mission.

In the future, the UH Manoa team will combine the research results with terrestrial-based observations of Titan’s atmosphere. (ANI)

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Brain region responsible for our sense of personal space identified

September 1, 2009 By Leave a Comment

London, August 31 (ANI): A new study led by neuroscientists at the California Institute of Technology (Caltech) may help improve the scientific understanding of the neural mechanisms involved in social behaviour, for it has pinpointed the brain structure that is responsible for our sense of personal space.

The rsearchers say that their findings may offer insight into autism, and other disorders where social distance is an issue.

The structure, the amygdala-a pair of almond-shaped regions located in the medial temporal lobes-was previously known to process strong negative emotions, such as anger and fear, and is considered the seat of emotion in the brain.

However, this is the first time that it has been linked rigorously to real-life human social interaction.

Ralph Adolphs, Bren Professor of Psychology and Neuroscience and professor of biology, and postdoctoral scholar Daniel P. Kennedy were able to make this link with the help of a unique patient, a 42-year-old woman known as SM, who has extensive damage to the amygdala on both sides of her brain.

“SM is unique, because she is one of only a handful of individuals in the world with such a clear bilateral lesion of the amygdala, which gives us an opportunity to study the role of the amygdala in humans,” Nature magazine quoted Kennedy, the lead author of the new report, as saying.

The researchers have revealed that SM has difficulty recognizing fear in the faces of others, and in judging the trustworthiness of someone, two consequences of amygdala lesions.

Adolphs, who has studied the patient for years, has also noticed that the very outgoing SM is almost too friendly, to the point of “violating” what others might perceive as their own personal space.

“She is extremely friendly, and she wants to approach people more than normal. It’s something that immediately becomes apparent as you interact with her,” says Kennedy.

Though previous studies on human subjects never revealed an association between the amygdala and personal space, the researchers knew from their knowledge of the lieterature that monkeys with amygdala lesions preferred to stay in closer proximity to other monkeys and humans than did healthy monkeys.

As part of their study, the researchers conducted an experiment in which the subject stands a predetermined distance from an experimenter, then walks toward the experimenter, and stops at the point where they feel most comfortable.

The chin-to-chin distance between the subject and the experimenter is determined with a digital laser measurer.

Among the 20 other subjects, the researchers observed that the average preferred distance was roughly two feet, while SM’s preferred distance was about one foot.

The team even observed that SM was at ease even at a nose-to-nose distance, and that her preferred distance didn’t change based on who the experimenter was and how well she knew them.

“Respecting someone’s space is a critical aspect of human social interaction, and something we do automatically and effortlessly. These findings suggest that the amygdala, because it is necessary for the strong feelings of discomfort that help to repel people from one another, plays a central role in this process. They also help to expand our understanding of the role of the amygdala in real-world social interactions,” Kennedy said.

The researchers later used a functional magnetic resonance imaging (fMRI) scanner to examine the activation of the amygdala in a separate group of healthy subjects who were told when an experimenter was either in close proximity or far away from them.

The subjects could not see, feel, or hear the experimenter while in the scanner, but still their amygdalae lit up when they believed the experimenter to be close by.

No such activity was detected when subjects thought the experimenter was on the other side of the room.

“It was just the idea of another person being there, or not, that triggered the amygdala,” Kennedy said.

He added: “(The Study shows that) the amygdala is involved in regulating social distance, independent of the specific sensory cues that are typically present when someone is standing close, like sounds, sights, and smells.”

He further said that the new findings might have relevance to studies of autism, a complex neurodevelopmental disorder that affects an individual’s ability to interact socially and communicate with others.

“We are really interested in looking at personal space in people with autism, especially given findings of amygdala dysfunction in autism. We know that some people with autism do have problems with personal space and have to be taught what it is and why it’s important,” he said.

Adding a word of caution, Kennedy also said: “It’s clear that amygdala dysfunction cannot account for all the social impairments in autism, but likely contributes to some of them and is definitely something that needs to be studied further.” (ANI)

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How neuronal activity is timed in brain’s memory-making circuits

May 30, 2009 By Leave a Comment

London, May 30 (ANI): Researchers at the California Institute of Technology (Caltech) have challenged the long-held assumption that theta oscillations-a type of prominent brain rhythm that orchestrates neuronal activity in the hippocampus-remain “in sync” across this key area for the formation of new memories.

In a new study, the researchers have found that instead of being in sync, theta oscillations actually sweep along the length of the hippocampus as travelling waves.

“It was assumed that activity in the hippocampus is synchronized throughout. But when we looked simultaneously at many different anatomical locations across the hippocampus, we found instead a systematic delay in neuronal activity from site to site. Instead of the whole structure oscillating at once, we see travelling waves that propagate across the hippocampus in a consistent direction, along its long axis,” Nature magazine quoted Evgueniy Lubenov, a postdoctoral scholar at the Center for Biological Circuit Design at Caltech, as saying.

Athanassios Siapas, associate professor of computation and neural systems and Bren Scholar at Caltech, added: “In other words, the hippocampus has a series of local time zones, just like we have on Earth.”
During the study, the researchers analysed the theta oscillations generated as rats move around and explore their environment.

The observed how and when rats’ neurons fired relative to their positions and to the phase of the theta oscillations.

They did so using multiple electrodes with recording sites, which enabled them to simultaneously isolate the spiking of many individual neurons.

“Each of these neurons fires only in a restricted region of space. Furthermore, the spikes don’t just happen any time-they pay attention to the phase of the ongoing theta oscillation. If you have access to the phase at which the neuron fired, you have additional information about where the rat was in space,” Lubenov said.

Upon combining the data about neuronal firing, oscillation phase and rat location, the researchers observed that neuronal activity indeed sweeps across the hippocampus in a wave, with its peak appearing in one region, then another, then another, rather than hitting the entire hippocampus in one synchronized pulse.

“This changes our notion of how spatial information is represented in the rat brain. It was believed that the firing of hippocampal neurons encodes the physical location of the rat in its environment-in other words, a point of physical space. Our findings suggest that what is encoded is actually a portion of the rat’s trajectory-that is, a segment of physical space,” Lubenov said.

Siapas added: “Such segments may be the elementary unit of hippocampal computation. Assume the path a rat takes in an environment is represented and stored as a sequence of point locations. If the rat visits the same location more than once, the representation becomes ambiguous. Representing the rat trajectory as a sequence of segments oriented in space resolves such ambiguities.”

The researchers say that the significance of their findings lies in the fact that they may prove helpful in understanding how information is transmitted from the hippocampus to other areas of the brain.

“Different portions of the hippocampus are connected to different areas in other parts of the brain. The fact that hippocampal activity forms a traveling wave means that these target areas receive inputs from the hippocampus in a specific sequence rather than all at once,” said Siapas.

The researcher also dismissed the suggestion that this behaviour is found only in rat brains, insisting that theta oscillations are ubiquitous in mammalian brains.

“I would expect the traveling-wave nature of theta oscillations to be a general finding, applicable to humans as well,” he said.

And while it is not known whether human hippocampal cells function as place cells, as they do in rats, “it may turn out to be the case that the human hippocampus plays a role in providing spatial cues that are important to episodic memory,” Lubenov said.

What we do know is that, by showing that theta oscillations travel across the hippocampus, the Caltech team will likely change the way neuroscientists think about how the hippocampus works. (ANI)

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Microchip-sized digital camera to provide vision for US military’s insect-sized aircraft

May 23, 2009 By Leave a Comment

London, May 23 (ANI): Scientists at the California Institute of Technology have developed a microchip-sized digital camera that can provide vision for the US military’s insect-sized aircraft.

The researchers say that the tiny camera is so light that it can be easily carried by the tiny surveillance drones.

They also say that the camera uses very little power, reports New Scientist magazine.

In today’s minicams, the image sensors and support circuitry are on separate microchips, and most of the power goes on communication between the chips.

Caltech’s Jet Propulsion Lab in Pasadena has squeezed all the components of a camera onto one low-power chip, according to a US patent filed last week.

The researchers say that the gadget can be radio-controlled via a secure frequency-hopping link from up to a kilometre away.

They attribute this invention to Pentagon and NASA funding. (ANI)

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How the body differentiates between a scorch and a scratch

May 20, 2009 By Leave a Comment

Washington, May 20 (ANI): American scientists have shed new light on how the body figures out whether it has been stuck by a pin or burnt by a match.

Researchers from the California Institute of Technology (Caltech) and the University of California, San Francisco (UCSF) have found that this sensory discrimination begins in the skin at the very earliest stages of neuronal information processing, with different populations of sensory neurons-called nociceptors-responding to different kinds of painful stimuli.

“Conventional wisdom was that the nociceptive neurons in the skin can’t tell the difference between heat and mechanical pain, like a pin prick. The idea was that the skin is a dumb sensor of anything unpleasant, and that higher brain areas disentangle one pain modality from another, to tell you if you’ve been scorched or scratched,” says David Anderson, Seymour Benzer Professor of Biology, a Howard Hughes Medical Institute (HHMI) Investigator, and one of the paper’s lead authors.

However, that was not sufficient to understand the control of pain-avoidance behavior, the researcher added.

“We were asking the cells what the cells can sense, not asking the animal what the cells can sense,” he said.

For their study, Anderson and his colleague Allan Basbaum, chair of the Department of Anatomy at UCSF, created a genetically engineered mouse in which specific populations of pain-sensing neurons could be selectively destroyed.

The researchers were then able to see if the mouse continued to respond to different types of stimuli by pulling its paw away, when exposed to a relatively gentle heat source or poked with a nylon fishing line.

When they killed off a certain population of nociceptor neurons, the mice stopped responding to being poked, but still responded to heat.

When the researchers injected a toxin to destroy a different population of neurons, the mice stopped responding to heat, but their sense of poke remained intact.

“This tells us that the fibers that mediate the response to being poked are neither necessary nor sufficient for a behavioral response to heat, and vice versa for the fibers that mediate the response to heat,” Anderson said. he researcher further said that neither of the two classes of sensory neurons seemed to be required for responding to a painful cold stimulus, like dry ice.

He said that research into pinpointing that population of cells was ongoing.

“This tells us that the discernment of different types of painful stimuli doesn’t happen only in the brain-it starts in the skin, which is therefore much smarter than we thought.

That’s a pretty heretical point of view,” said Anderson.

The study has been published in the early online edition of the Proceedings of the National Academy of Sciences (PNAS). (ANI)

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How ‘angel’ and ‘devil’ brain areas interact while exercising self-control

May 3, 2009 By Leave a Comment

Washington, May 1 (ANI): When on diet, skipping a favourite calorie-laden dessert can take a whole lot of self-control – an ability that comes easier to some people than others. Now, US scientists have identified an “angel” centre in the brain which holds back another “devil” area to stop individuals giving in to temptation.

Scientists from the California Institute of Technology (Caltech) have uncovered differences in the brains of people who are able to exercise self-control versus those who find it almost impossible.

The key in the research is, while everyone uses the same single area of the brain to make these sorts of value-laden decisions, a second brain region modulates the activity of the first region in people with good self-control, allowing them to weigh more abstract factors like healthiness – in addition to basic desires such as taste to make a better overall choice.

The study has been published in the May 1 issue of the journal Science.

“A very basic question in economics, psychology, and even religion, is why some people can exercise self-control but others cannot,” notes Antonio Rangel, a Caltech associate professor of economics and the paper’s principal investigator.

“From the perspective of modern neuroscience, the question becomes, ‘What is special about the circuitry of brains that can exercise good behavioral self-control?’ This paper studies this question in the context of dieting decisions and provides an important insight,” he added.

That insight was the result of an innovative experiment: A group of volunteers- all self-reported dieters- were shown photos of 50 foods, including everything from Snickers bars to Jello to cauliflower. The participants were asked to rate each of the foods based on how good they thought that food would taste. Afterwards, they were shown the same slides again and asked to rate each of the foods based on its supposed health benefits.

From those ratings, the researchers selected an “index food” for each volunteer – a food that fell about in the middle of the pack in terms of tastiness and supposed health benefits.

The participant was then shown the 50 items one final time and was asked to choose between it and the index item. (To keep the choosers “honest” without forcing them to eat 50 different foods in one sitting, the researchers would randomly select a number corresponding to one of the slides, and the participant would have to eat whichever food had been chosen at that point.)

All three viewings of the slides were done with the participant inside an MRI scanner, so that the blood-oxygen level dependent signal (a proxy for neuronal activity) in specific areas of the brain could be measured.

After all the choices had been made, the researchers were able to pick out 19 volunteers who showed a significant amount of dietary self-control in their choices, picking mostly healthy foods, regardless of taste. They were also able to identify 18 additional volunteers who showed very little self-control, picking what they believed to be the tastier food most of the time, regardless of its nutritional value.

When they looked at the brain scans of the participants, researchers found significant differences in the brain activity of the self-control group as compared to the non-self-controllers.

Earlier studies have shown that value-based decisions are reflected in the activity of a region in the brain called the ventromedial prefrontal cortex, or vmPFC.

If activity in the vmPFC goes down, explains Todd Hare, a postdoctoral scholar in neuroeconomics and the first author on the Science paper, “it means the person is probably going to say no to that item; if it goes up, they’re likely to choose that item.”

In the non-self-controllers, Rangel notes, the vmPFC seemed to only take the taste of the food into consideration in making a decision.

“In the case of good self-controllers, however, another area of the brain-called the dorsolateral prefrontal cortex [DLPFC]–becomes active, and modulates the basic value signals so that the self-controllers can also incorporate health considerations into their decisions,” he explains. (ANI)

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New enzymes for cheaper biofuel production engineered

March 24, 2009 By Leave a Comment

Washington, Mar 24 (ANI): Researchers at the California Institute of Technology (Caltech) and world-leading gene-synthesis company DNA2.0 have created new enzymes for cheaper biofuel production.

Biofuels are made by converting renewable materials-for example, corn kernels, wood chips left over from pulp and paper production, prairie grasses, and even garbage-into fuels and chemicals.

Frances H. Arnold, the Dick and Barbara Dickinson Professor of Chemical Engineering and Biochemistry at Caltech, and her colleagues have constructed 15 new highly stable fungal enzyme catalysts that efficiently break down cellulose into sugars at high temperatures.

Cellulose is the world’s most abundant organic material and cheapest form of solar-energy storage.

Plant sugars are easily converted into a variety of renewable fuels such as ethanol or butanol.

Earlier, less than 10 such fungal cellobiohydrolase II enzymes were known.

But the new enzymes, not only boast remarkable stabilities, but also degrade cellulose over a wide range of conditions.

Most biofuels used today are made from the fermentation of starch from corn kernels. That process, although simple, is costly because of the high price of the corn kernels themselves.

Agricultural waste, such as corn stover (the leaves, stalks, and stripped cobs of corn plants, left over after harvest), is cheap. These materials are largely composed of cellulose, the chief component of plant-cell walls. Cellulose is far tougher to break down than starch.

An additional complication is that while the fermentation reaction that breaks down cornstarch needs just one enzyme, the degradation of cellulose requires a whole suite of enzymes, or cellulases, working in concert.

Arnold and Caltech postdoctoral scholar Pete Heinzelman created the 15 new enzymes using a process called structure-guided recombination.

Using a computer program to design where the genes recombine, the researchers “mated” the sequences of three known fungal cellulases to make more than 6,000 progeny sequences that were different from any of the parents, yet encoded proteins with the same structure and cellulose-degradation ability.

After analysing the enzymes encoded by a small subset of those sequences, the researchers could predict which of the more than 6,000 possible new enzymes would be the most stable, especially under higher temperatures (a characteristic called thermostability).

“Enzymes that are highly thermostable also tend to last for a long time, even at lower temperatures. And, longer-lasting enzymes break down more cellulose, leading to lower cost,” said Arnold.

Using the computer-generated sequences, researchers synthesized actual DNA sequences, which were transferred into yeast in Arnold’s laboratory. The yeast produced the enzymes, which were then tested for their cellulose-degrading ability and efficiency.

Each of the 15 new cellulases was more stable, worked at significantly higher temperatures (70 to 75 degrees Celsius), and degraded more cellulose than the parent enzymes at those temperatures.

“This is a really nice demonstration of the power of synthetic biology,” said Arnold.

The study is published in the early edition of the Proceedings of the National Academy of Sciences. (ANI)

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