NIGMS and Scholastic bring you our latest issue of Pathways, which focuses on superbugs—infectious microbes that can’t be fought off with medicines. Viruses that can’t be prevented with vaccines, such as the common cold, and antibiotic-resistant bacteria both fall into this category.
Pathways, designed for students in grades 6 through 12, is a collection of free resources that teaches students about basic science and its importance to health, as well as exciting research careers.
Sepsis is the body’s overactive and extreme response to an infection. It’s unpredictable, can progress rapidly, and affects more than 1.7 million people in the United States each year. Without prompt treatment, it can lead to tissue damage, organ failure, and death. NIGMS supports state-of-the-art sepsis research, including the development of rapid diagnostics and new therapeutics. September is Sepsis Awareness Month, and we’re highlighting a few resources that offer more information about this condition.
Our infographic provides details at a glance on basic statistics and the future of sepsis research. It’s also available in Spanish.
A cone snail shell. Credit: Kerry Matz, University of Utah.
Over the years, scientists have discovered many compounds in nature that have led to the development of medications. For instance, the molecular structure for aspirin came from willow tree bark, and penicillin was found in a type of mold. And uses of natural products aren’t limited to medicine cabinet staples and antibiotics. A cancer drug was originally found in the bark of the Pacific yew tree, and a medication for chronic pain relief was first isolated from cone snail venom. Today, NIGMS supports scientists in the earliest stages of investigating natural products made by plants, fungi, bacteria, and animals. The results could inform future research and bring advances to the field of medicine.
Sepsis is a serious medical condition caused by an overwhelming response to infection that damages tissues and organs. It’s unpredictable, progresses quickly, can strike anyone, and is a leading cause of hospital-related deaths. In the U.S. alone, nearly 270,000 people die each year from sepsis. Those who survive sepsis often end up in the hospital again, and some have long-term health complications. Early treatment is key for many patients to survive sepsis, yet doctors can’t easily diagnose it because it’s so complex and each patient is different.
Despite decades of research, sepsis remains a poorly understood condition with limited diagnostic tools and treatment. To tackle these obstacles, scientists Vincent Liu, Christopher Seymour, and Hallie Prescott have started using a “big data” approach, which relies on complex computer programs to sift through huge amounts of information. In this case, the computers analyze data such as demographic information, vital signs, and routine blood tests in the electronic health records of sepsis patients. The goal is to find patterns in the data that might help doctors understand, predict, and treat sepsis more effectively.
Research on how diet impacts the gut microbiota has rapidly expanded in the last several years. Studies show that diets rich in red meat are linked to diseases such as colon cancer and heart disease. In both mice and humans, researchers have recently discovered differences in the gut microbiota of those who eat diets rich in red meat compared with those who don’t. This is likely because of a sugar molecule in the red meat, called N-glycolylneuraminic acid (Neu5Gc), that our bodies can’t break down. Researchers believe the human immune system sees Neu5Gc as foreign. This triggers the immune system, causing inflammation in the body, and possibly leads to disease over time.
DNA, with its double-helix shape, is the stuff of genes. But genes themselves are only “recipes” for protein molecules, which are molecules that do the real heavy lifting (or do much of the work) inside cells.
Artist interpretation of RNAP grasping and unwinding a DNA double helix. Credit: Wei Lin and Richard H. Ebright.
Here’s how it works. A molecular machine called RNA polymerase (RNAP) travels along DNA to find a place where a gene begins. RNAP uses a crab-claw-like structure to grasp and unwind the DNA double helix at that spot. RNAP then copies (“transcribes”) the gene into messenger RNA (mRNA), a molecule similar to DNA.
The mRNA molecule travels to one of the cell’s many protein-making factories (ribosomes), which use the mRNA message as instructions for making a specific protein.
Cataloging the human microbiome—the complete collection of bacteria, fungi, archaea, protists, and viruses that live in and on our bodies—is an enormous task. Most estimates put the number of organisms who call us home on par with the number of our own cells. Imagine trying to figure out how the billions of critters influence each other and, ultimately, impact our health. Elhanan Borenstein, a computer scientist-cum-genomicist at the University of Washington, and his team are not only tackling this difficult challenge, they are also trying to obtain a systems-level understanding of the collective effect of all of the genes, proteins, and metabolites produced by the numerous species within the microbiome.
You’ve likely heard some variation of the statistic that there are at least as many microbial cells in our body as human cells. You may have also heard that the microscopic bugs that live in our guts, on our skins, and every crevice they can find, collectively referred to as the human microbiome, are implicated in human health. But do these bacteria, fungi, archaea, protists, and viruses cause disease, or are the specific populations of microbes inside us a result of our state of health? That’s the question that drives the research in the lab of Andrew Goodman , associate professor of microbial pathogenesis at Yale University.
Suppose you were a police detective investigating a robbery. You’d appreciate having a stack of photographs of the crime in progress, but you’d be even happier if you had a detailed movie of the robbery. Then, you could see what happened and when. Research on cells is somewhat like this. Until recently, scientists could take snapshots of cells in action, but they had trouble recording what cells were doing over time. They were getting an incomplete picture of the events occurring in cells.
Researchers have started solving this problem by combining some old knowledge—that DNA is spectacularly good at storing information—with a popular new research tool called CRISPR. CRISPR (clustered regularly interspaced short palindromic repeats) is an immune system feature in bacteria that helps them to remember and destroy viruses that infect them. CRISPR can change DNA sequences in precise ways; and it’s programmable, meaning that researchers can tell CRISPR where to make a change on a DNA strand, and even what kind of change to make. By linking cellular events to CRISPR, researchers can make something like a movie that captures many pieces of information in the form of DNA changes that researchers can read back later. These pieces of information include timing, duration, and intensity of events, such as the turning on of a specific protein pathway or the exposure of the cell to pathogens (i.e. germs). Here, we look at some of the ways NIGMS-funded research teams and others are using CRISPR to capture these kinds of data within DNA sequences.
An audio recorder stores audio signals into a magnetic tape medium (left). Similarly, a microscopic data recorder stores biological signals into a CRISPR tape in bacteria (middle). An enormous amount of information can be stored across multiple bacterial cells (right). Credit: Wang Lab/Columbia University Medical Center.
Round and Round: mSCRIBE Creates a Continuous Recording Loop
MIT bioengineers, led by Timothy Lu, have devised a memory storage system illustrated here as a DNA-embedded meter that records the activity of a signaling pathway in a human cell. Credit: Timothy Lu lab, MIT.
CRISPR uses an enzyme called Cas9 like a surgical knife, to slice both strands of a cell’s DNA at precise points. A cut like this sends the cell scrambling to repair the damage. Often, the repair effort results in changes, or errors, in the repaired strand that pile up at a known rate. Timothy Lu and his colleagues at the Massachusetts Institute of Technology (MIT) decided to turn this cut-repair-error system into a way to record certain events inside a cell. They call their method mSCRIBE (mammalian synthetic cellular recorder integrating biological events).