Category Archives: Life Science

Biological Molecular Motors

bio

Image: The biomolecular portal motor of bacteriophage PHI-29 (yellow) compresses the coiled DNA into the viral capsid at 6,000 times its normal pressure. (courtesy the Bustamante group)

Start Your Protein Engines by David Pescovitz:

Oster and his research group investigate the physics and chemistry behind great engineering mysteries of the natural world, from protein motors to cell motility to how bacteria form thriving populations that aren’t so different from ant colonies, or even human societies.
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Working with UC Berkeley professor Carlos Bustamante, researchers have also studied the motor that packs a virus’s DNA so tightly that it can be injected into a hijacked cell at ten times the pressure of a cork shooting out of a champagne bottle. And they’ve modeled the donut-shaped molecular motors that move along DNA strands during replication.

In the closing paragraph Dr. Oster is quoted on the use of models, which reminds me a the quote from Dr. George Box: All models are wrong, some are useful.

Other articles from from the most recent ScienceMatters@Berkeley: The New New Math of String Theory and Molecular Rules Of Engagement. Also see previous article: The Cellular Mechanic.

Cancer Scientists Find Worm Link

Cancer scientists find worm link by Matt McGrath:

Now scientists in California have found that when they removed this same protein from the tiny worm C. elegans, the worms lived up to 30% longer than normal.

The scientists deduced that a lack of this protein might mean that humans also live longer, but with an increased risk of getting cancer.

The researchers think the protein’s dual function raises another important question: does the presence of this protein ensure a short but cancer-free existence for some people?

Ocean Life

Iridescent nudibranch

Photo: This iridescent nudibranch looks like a creature from another planet. Larger photo.

The United States National Oceanic and Atmospheric Administration (part of the U.S. Department of Commerce?) includes a huge photo and videocast gallery including: invertebrates, vertebrates and seafloor.

Also see an exploding volcano under the sea for the first time ever, from the:Submarine Ring of Fire 2006 Exploration, NOAA Vents Program.

Entirely New Antibiotic Developed

Potent antibiotic to target MRSA

A potent antibiotic which kills many bacteria, including MRSA, has been discovered. Scientists with Merck, isolated platensimycin from a sample of South African soil and have developed an antibiotic based on that discovery.

If the compound passes clinical trials it will become only the third entirely new antibiotic developed in the last four decades.

Details in the journal Nature reveal the antibiotic works in a completely different way to all others.

It acts to block enzymes involved in the synthesis of fatty acids, which bacteria need to construct cell membranes.

Methicillin-resistant Staphylococcus Aureus (MRSA) is a type of bacteria that is resistant to certain antibiotics, including: methicillin and other more common antibiotics such as oxacillin, penicillin and amoxicillin. Staph infections, including MRSA, occur most frequently among persons in hospitals and healthcare facilities who have weakened immune systems. More information on MRSA is available from the United States Center for Disease Control and Prevention.

Scientific Misinformation

Lactic Acid Is Not Muscles’ Foe, It’s Fuel by Gina Kolata:

But that, it turns out, is all wrong. Lactic acid is actually a fuel, not a caustic waste product. Muscles make it deliberately, producing it from glucose, and they burn it to obtain energy.
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“I had huge fights, I had terrible trouble getting my grants funded, I had my papers rejected,” Dr. Brooks recalled. But he soldiered on, conducting more elaborate studies with rats and, years later, moving on to humans. Every time, with every study, his results were consistent with his radical idea.

Eventually, other researchers confirmed the work. And gradually, the thinking among exercise physiologists began to change.

Wallaby Milk Cure

Fighting Superbugs with Milk

Cocks has found that the mother’s milk contains a molecule that is 100 times more effective against Gram-negative bacteria such as E. coli than the most potent form of penicillin. The molecule, called AGG01, also kills four types of Gram-positive bacteria and one type of fungus. The work was presented at the US Biotechnology Industry Organization 2006 meeting in Chicago last week.

Antibiotic Discovery Stagnates

Bad Bugs, No Drugs As Antibiotic Discovery Stagnates . . . A Public Health Crisis Brews by the Infectious Diseases Society of America. The site includes a 37 page white paper.

A multi-pronged approach is needed to limit the impact of antibiotic resistance on patients and the public. These efforts include educating physicians, patients, and parents about the appropriate use of antibiotics, developing and applying infection control and immunization policies and practices to prevent transmission, surveying clinical and prescription data, and developing safer alternatives to antibiotic uses in agriculture.

The purpose of this document, however, is to call attention to a frightening twist in the antibiotic resistance problem that has not received adequate attention from federal policymakers: The pharmaceutical pipeline for new antibiotics is drying up.

Facts About Antibiotic Resistance:

The total cost of antimicrobial resistance to U.S. society is nearly $5 billion annually, according to the Institute of Medicine (IOM). Treating resistant pathogens often requires more expensive drugs and extended hospital stays.

More on the overuse of antibiotics – which creates drug resistance
Previous posts on antibiotics

Nanospheres Targeting Cancer at MIT

Nanospheres targeting cancer cells

Single-Shot Chemo – Nanospheres that target cancer cells and gradually release drugs could make treatment safer and more effective

Photo – Three prostate cancer cells have taken up fluorescently labeled nanoparticles (shown in red). The cells’ nuclei and cytoskeletons are stained blue and green, respectively. By Omid Farokhzad and Robert Langer at MIT.

A key to the nanoparticles’ effectiveness is the ability of their RNA strands to bind to a cancer cell membrane. The cell then pulls the particles inside. Having the particles inside the cell has two advantages: it gets the drug where it needs to be to kill the cells, and it decreases the concentration of the drug outside the cancer cells, thereby decreasing toxicity to healthy tissue. The fact that the polymer releases the drug gradually also helps — the drug is released over the hours or days it takes for the particles to be pulled into cells, where it continues to be released, killing the cells.
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Eventually, the MIT-Harvard researchers hope to design nanoparticles that can be injected into the bloodstream, from which they could seek out cancer cells anywhere in the body, making it possible to treat late-stage metastasized cancer. “Even though this represents a small percentage of patients that actually have the disease, these are the ones that have no therapeutic option available to them,” Farokhzad says.

More life science related posts and medical related posts.

Singapore woos top scientists with new labs

Singapore woos top scientists with new labs, research money by Paul Elias:

Singapore’s siren song is growing increasingly more irresistible for scientists, especially stem cell researchers who feel stifled by the U.S. government’s restrictions on their field.

Two prominent California scientists are the latest to defect to the Asian city-state, announcing earlier this month that they, too, had fallen for its glittering acres of new laboratories outfitted with the latest gizmos.

They weren’t the first defections, and Singapore officials at the Biotechnology Organization’s annual convention in Chicago this week promise they won’t be the last.

Other Asian countries, including Japan, South Korea and even China, are also here touting their burgeoning biotechnology spending to the 20,000 scientists and biotechnology executives attending the conference.
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In all, the country has managed to recruit about 50 senior scientists — far short of what it needs, but a start for a tiny country of 4.5 million people off the tip of Malaysia.

Another 1,800 younger scientists from all corners of the world staff the Biopolis laboratories, which were built with $290 million in government funding and another $400 million in private investment by the two dozen biotechnology companies based there. Biopolis opened in 2003 and contains seven buildings spread over 10 acres and connected by sky bridges

Nobel Laureate Discusses Protein Power

Nobel Laureate discusses protein power – Podcast

Nobel Laureate Professor Robert Huber visited the The University of Queensland – Brisbane to discuss the future of biomedicine.

He presented the studies that earned him the Nobel Prize for Chemistry in 1988 and discussed the future of protein crystallography to reduce several diseases such as influenza and cancer.

Nobel Prize