skip to main content

Search for: All records

Creators/Authors contains: "Neu, Heather M."

Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher. Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?

Some links on this page may take you to non-federal websites. Their policies may differ from this site.

  1. Municipal drinking water, regulated by the Environmental Protection Agency via the Safe Drinking Water act, has long been assumed to be contaminant-free. However, crises related to drinking water have emerged, most notably the “Flint Water Crisis” in Flint, MI, where high levels of lead (Pb) were detected in the area’s water. Much of the water-sampling data collected in Flint was obtained by “Citizen Scientists” working closely with a team of researchers at Virginia Tech, who used the analytical technique of Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to quantify metal ions present in the water. Inspired by these efforts, we developed adaptable public water testing outreach efforts, led by students in Baltimore city (Middle School, High School, and College), to test the city’s drinking water. These “student-scientists” read news and scientific articles to understand the public health impact of lead in drinking water and the analytical approaches scientists use to detect metal ions in water. The students then developed a written “water collection protocol” and sought participation from colleagues (other students, faculty, and staff) who collected their home drinking water to be tested. The student scientists prepared and analyzed samples for lead (Pb) as well as copper (Cu), iron (Fe), and zinc (Zn) metal ions commonly found in drinking water, to be tested via ICP-MS. Data were then plotted onto a map of Baltimore City, with the metal levels indicated for each Zip code. This outreach event connects science to real-life news events while teaching analytical methodology and can be tailored to students at various stages of their education. 
    more » « less
  2. Targeting Clostridium difficile infection is challenging because treatment options are limited, and high recurrence rates are common. One reason for this is that hypervirulent C. difficile strains often have a binary toxin termed the C. difficile toxin, in addition to the enterotoxins TsdA and TsdB. The C. difficile toxin has an enzymatic component, termed CDTa, and a pore-forming or delivery subunit termed CDTb. CDTb was characterized here using a combination of single-particle cryoelectron microscopy, X-ray crystallography, NMR, and other biophysical methods. In the absence of CDTa, 2 di-heptamer structures for activated CDTb (1.0 MDa) were solved at atomic resolution, including a symmetric ( Sym CDTb; 3.14 Å) and an asymmetric form ( Asym CDTb; 2.84 Å). Roles played by 2 receptor-binding domains of activated CDTb were of particular interest since the receptor-binding domain 1 lacks sequence homology to any other known toxin, and the receptor-binding domain 2 is completely absent in other well-studied heptameric toxins (i.e., anthrax). For Asym CDTb, a Ca 2+ binding site was discovered in the first receptor-binding domain that is important for its stability, and the second receptor-binding domain was found to be critical for host cell toxicity and the di-heptamer fold for both forms of activated CDTb. Together, these studies represent a starting point for developing structure-based drug-design strategies to target the most severe strains of C. difficile . 
    more » « less