DNA
Powerful Antibiotics Found in Dirt

Caption: Researchers found a new class of antibiotics in a collection of about 2,000 soil samples.
Credit: Sean Brady, The Rockefeller University, New York City
Many of us think of soil as lifeless dirt. But, in fact, soil is teeming with a rich array of life: microbial life. And some of those tiny, dirt-dwelling microorganisms—bacteria that produce antibiotic compounds that are highly toxic to other bacteria—may provide us with valuable leads for developing the new drugs we so urgently need to fight antibiotic-resistant infections.
Recently, NIH-funded researchers discovered a new class of antibiotics, called malacidins, by analyzing the DNA of the bacteria living in more than 2,000 soil samples, including many sent by citizen scientists living all across the United States [1]. While more work is needed before malacidins can be tried in humans, the compounds successfully killed several types of multidrug-resistant bacteria in laboratory tests. Most impressive was the ability of malacadins to wipe out methicillin-resistant Staphylococcus aureus (MRSA) skin infections in rats. Often referred to as a “super bug,” MRSA threatens the lives of tens of thousands of Americans each year [2].
Posted In: Health, Science, technology
Tags: antibiotic resistance, antibiotic treatment, antibiotics, bacteria, calcium-dependent antibiotics, citizen science, DNA, Drugs from Dirt, malacidins, MRSA, multi-drug resistance, multidrug resistant bacteria, soil, soil-dwelling bacteria, Staphylococcus aureus, Streptomyces albus, super bug
Sequencing Human Genome with Pocket-Sized “Nanopore” Device

Caption: MinION sequencing device plugged into a laptop/Oxford Nanopore Technologies
It’s hard to believe, but it’s been almost 15 years since we successfully completed the Human Genome Project, ahead of schedule and under budget. I was proud to stand with my international colleagues in a celebration at the Library of Congress on April 14, 2003 (which happens to be my birthday), to announce that we had stitched together the very first reference sequence of the human genome at a total cost of about $400 million. As remarkable as that achievement was, it was just the beginning of our ongoing effort to understand the human genome, and to use that understanding to improve human health.
That first reference human genome was sequenced using automated machines that were the size of small phone booths. Since then, breathtaking progress has been made in developing innovative technologies that have made DNA sequencing far easier, faster, and more affordable. Now, a report in Nature Biotechnology highlights the latest advance: the sequencing and assembly of a human genome using a pocket-sized device [1]. It was generated using several “nanopore” devices that can be purchased online with a “starter kit” for just $1,000. In fact, this new genome sequence—completed in a matter of weeks—includes some notoriously hard-to-sequence stretches of DNA, filling several key gaps in our original reference genome.
Posted In: Health, Science, technology
Tags: biotechnology, Biowulf, DNA, DNA sequencing, Ebola virus, genome assembly, hand-held sequencing device, human genome, Human Genome Project, International Space Station, MinION, nanopore sequencing, Oxford Nanopore Technologies, precision medicine, repetitive DNA, telomeres, Zika virus
Creative Minds: A New Way to Look at Cancer
Inside our cells, strands of DNA wrap around spool-like histone proteins to form a DNA-histone complex called chromatin. Bradley Bernstein, a pathologist at Massachusetts General Hospital, Harvard University, and Broad Institute, has always been fascinated by this process. What interests him is the fact that an approximately 6-foot-long strand of DNA can be folded and packed into orderly chromatin structures inside a cell nucleus that’s just 0.0002 inch wide.
Bernstein’s fascination with DNA packaging led to the recent major discovery that, when chromatin misfolds in brain cells, it can activate a gene associated with the cancer glioma [1]. This suggested a new cancer-causing mechanism that does not require specific DNA mutations. Now, with a 2016 NIH Director’s Pioneer Award, Bernstein is taking a closer look at how misfolded and unstable chromatin can drive tumor formation, and what that means for treating cancer.
Posted In: Health, Science, technology
Tags: 2016 NIH Director’s Pioneer Award, astrocytoma, brain cancer, cancer, cancer epigenetics, cancer epigenome, central nervous system cancers, chromatin, chromatin structure, DNA, DNA folding, DNA methylation, DNA packaging, epigenetics, epigenome, epigenomics, glioblastoma, glioma, histones