Female brown recluse spider. Credit Matt Bertone, North Carolina State University.
This Halloween, you’re not likely to see many trick-or-treaters dressed as spiders. Google Trends pegs “Spider” as the 87th most searched-for Halloween costume, right between “Hippie” and “The Renaissance.” But don’t let your guard down. Spiders are everywhere.
“I grew up on a farm in Indiana and had the luxury of exploring and turning over rocks and being curious. Any feelings of being grossed out by spiders were rapidly replaced by my feelings of awe for how amazing and diverse these creatures are.”– Greta Binford”
More than 46,000 species of spiders creepy crawl across the globe, on every continent except Antarctica. Each species produces a venom composed of an average of 500 distinct toxins, putting the conservative estimate of unique venom compounds at more than 22 million. This staggering diversity of venoms, collectively referred to as the venome, has only begun to be explored. Continue reading “Exploring the Evolution of Spider Venom to Improve Human Health”
The outside of every cell on Earth—from the cells in your body to single-celled microorganisms—is blanketed with a coat of carbohydrates, or sugar molecules, that extend from the cell surface, branching off and bending as they interface with the extra-cellular space. The specific patterns in which these carbohydrates are arranged serve as an ID code that help cells recognize each other. For example, human liver cells have one pattern, while human red blood cells another. Certain diseases can even alter the pattern of surface carbohydrates, which is one way the body can recognize damaged cells. On foreign cells, including invading bacteria such as Streptococcus pneumoniae, the carbohydrate coat is even more distinct.
Laura Kiessling, a professor of chemistry at the University of Wisconsin, Madison, studies how carbohydrate coats are assembled and how cells use these coats to tell friend from foe. The implications of her research suggest strategies for targeting tumors, fighting diseases of inflammation and, as she discusses in this video, developing new classes of antibiotics.
A family of proteins abbreviated SEDS (bright, pink) help build bacterial cell walls, so they are a potential target for new antibiotic drugs. Credit: Rudner lab, Harvard Medical School.
Scientists have identified a new family of proteins that, like the targets of penicillin, help bacteria build their cell walls. The finding might reveal a new strategy for treating a range of bacterial diseases.
The protein family is nicknamed SEDS, because its members help control the shape, elongation, division and spore formation of bacterial cells. Now researchers have proof that SEDS proteins also play a role in constructing cell walls. This image shows the movement of a molecular machine that contains a SEDS protein as it constructs hoops of bacterial cell wall material.
Any molecule involved in building or maintaining cell walls is of immediate interest as a possible target for antibiotic drugs. That’s because animals, including humans, don’t have cell walls—we have cell membranes instead. So disabling cell walls, which bacteria need to survive, is a good way to kill bacteria without harming patients.
This strategy has worked for the first antibiotic drug, penicillin (and its many derivatives), for some 75 years. Now, many strains of bacteria have evolved to resist penicillins—and other antibiotics—making the drugs less effective.
According to the Centers for Disease Control and Prevention, drug-resistant strains of bacteria infect at least 2 million people, killing more than 20,000 of them in the U.S. every year. Identifying potential new drug targets, like SEDS proteins, is part of a multi-faceted approach to combating drug-resistant bacteria.
What do you get when you mix a room full of scientists with a classroom full of students who have questions about cells? Cell Day 2016! During this free web chat, middle and high school students will have the opportunity to ask our scientists at NIGMS about cell biology, biochemistry, research careers and more. Join us on Thursday, November 3 anytime from 10 a.m. to 3 p.m. EDT. Registration (no longer available) is now open.