Emory Professor of Chemistry Vincent Conticello was quoted in Chemistry World discussing protein materials:
“the development of silks has several significant challenges including high hydrophobicity, low solubility and limited functionality for post-processing modification. In contrast, the coiled-coil materials described here can be maintained in a soluble state and undergo a conformational conversion to β-sheets under surprisingly mild conditions. The resultant fibres can be drawn and cross-linked using standard methodologies to afford highly stable and mechanically robust materials”.
Bill Wuest has been named one of three recipients of the 2017 ACS Infectious Disease Young Investigator Award given by ACS Infectious Diseases and the ACS Division of Biological Chemistry. Winners received a plaque, an award of $1,000, and up to $500 in travel reimbursement to attend the 2017 ACS Fall National Meeting in Washington, D.C., and present at an ACS Division of Biological Chemistry symposium in their honor. In addition, they were honored at the ACS Infectious Diseases Young Investigator Awards Symposium during the meeting.
Brooke Howell interviewed Dr. Wuest regarding the honor.
What’s next in your research?
With my group’s recent move to Emory University, I felt that this would be an ideal time to expand our research focus beyond bacterial biofilms and look into other areas antibacterial research. More specifically, we are looking to expand our “narrow-spectrum” research program with a focus on Pseudomonad-specific therapies in collaboration with the CF-Atlanta group. Likewise, we also plan to work closely with the Antibiotic Resistance Center here at Emory to further investigate mechanisms of antibiotic resistance development by both using our current, and continuing to develop, chemical probes.
Research from the research group of Dr. David Lynn is featured on the cover of the latest issue of Organic and Biomolecular Chemistry. OBC is a weekly journal for the publication of highly significant original research and reviews in all areas of organic chemistry, including organic synthesis, physical organic chemistry, supramolecular chemistry and bioorganic chemistry.
The cover art is related to the article “Amyloid scaffolds as alternative chlorosomes” contained in the issue. Recent graduate Rolando Rengifo is first author with Noel Li, Anthony Sementilli, and David G. Lynn as additional authors.
Ian Pavelich (Dunham Group) has been awarded an Advancing Science in America or ARCS Fellowship. The ARCS Foundation advances science and technology in the United States by providing financial awards to academically outstanding U.S. citizens studying to complete degrees in science, engineering and medical research. The awards are focused on helping researchers at the startup or “seed stage” of their work and discovery.
Ian’s project is titled “Molecular mechanisms of antibiotic tolerance.” “The project focuses on identifying the molecular mechanism for how pathogenic bacteria confer an antibiotic tolerance phenotype or behavior without the requirement for genetic mutations,” says Ian. “Currently, we’re attempting to identify how different stresses, like classes of antibiotics, activate different enzymes that trigger antibiotic tolerance.” The research has potential implications for the future of public health: “As modern medicine would be impossible without the use of antibiotics, further investigating these novel systems as potential new antimicrobial strategies is incredibly important.”
The ARCS Award is an unrestricted $7,500 award given directly to the scientist and may be renewed for up to three years. When asked how the ARCS Award will affect his work, Ian says: “I think that ARCS will provide a layer of flexibility in how we choose to answer the questions targeted by my research. I am extremely grateful that the ARCS committee granted me these funds, and with them I aim to expand the scope of my studies using more interdisciplinary approaches. I also plan to use funds to attend a range of diverse conferences.”
Outside the lab, Ian has been involved in outreach at Emory, working on a chemistry event during the annual Science Olympiad for area high school students that focused on fundamental gas laws and their quantitative uses. Ian’s ties to Emory go beyond chemistry, too. This month, his partner will be joining the Political Science Department graduate program at Emory: “we’ll be doing our PhDs side by side!”
Yang Liu (Salaita Group) is bringing new techniques to the emerging field of mechanobiology; at the same time, he’s returning to his roots.
Literally. As in, plants.
Yang’s father is an academic biologist studying agriculture in China.
“I think in the beginning, my dad really wanted me to be a biologist,” says Yang. “But normally kids don’t want to pursue the same career path as their parents.”
As an undergraduate in China, Yang started out studying mechanical engineering. Then, he attended a general chemistry lecture with a famous chemistry professor who made a convincing case for the importance of the discipline. “He said, ‘chemistry is the central science connecting physical sciences, life sciences and applied sciences all together,’’ says Yang. “And I was so fascinated by it. And I changed my major.”
At Emory, Yang joined the lab of Khalid Salaita. His research in the Salaita Group takes a novel approach to a common scientific question: how does the immune system recognizes and eliminates “invaders”, such as pathogens or cancer cells? Most research explores how chemical signals mediate this process. Yang’s work expands on existing work in the Salaita Group that focuses on mechanical signaling—the way that immune cells physically probe their targets within the body. “Cells can touch and apply forces to one another,” explains Yang, a process he refers to as a “handshake.” Yang’s research develops tools that allow scientists to “see” these kinds of physical interactions.
Specifically, Yang has developed a technique named molecular tension fluorescence microscopy (MTFM) that employs single elastic molecules—DNA, protein, and polymer— as sensors to visualize membrane receptor mediated forces at the piconewton level. “One piconewton is the weight of one trillionth of an apple and surprisingly, pN forces regulate biochemical signaling pathways,” says Yang. These forces are too small for scientists to measure using conventional methods. Existing tools aren’t sensitive enough or they are inefficient.
“Until our method kicks in,” says Yang.
Yang has combined nanotechnology and the “easy” surface chemistry of gold nanoparticles to make MTFM probes more effective. “These gold particle sensors are spring scales at nanoscale ,” says Yang. “Compared to previous techniques, these probes are of significantly enhanced sensitivity, stability and amenable for detecting forces mediated by almost all kinds of cell receptors.”
The improvements have caught the attention of researchers in other Emory units—and even nationally and internationally. Yang has collaborated with the Evavold Lab in the Department of Immunology at Emory to help them measure mechanical forces mediated by different immune cells. He also has collaborators from as far away as New York and Germany.
Regarding these collaborations, Yang says: “The need to be trained [to use this method] is very high. The method is not hard, it’s easy. So people usually spend a few days and they should be able to master it…and we still maintain quite tight collaboration. We not only teach them how to make it, we actually get involved in the scientific questions they care about and continue this collaboration.”
Recently, Yang’s success in developing the new method was recognized with the department’s highest graduate student honor, the Quayle Outstanding Student Award. Speaking of Yang’s progress shortly after the award ceremony, advisor Khalid Salaita praised Yang’s work ethic as well as his science: “Yang was a real pleasure to have in the lab. He was incredibly thoughtful, well read, and intensely motivated. More than anyone else I’ve worked with, Yang displayed a keen instinct for experimental design. He spent countless hours in the dark microscope room collecting data and working around the clock fueled up with his favorite bbq Pringles and excited by the science.”
The award ceremony was followed swiftly by another milestone—a successful PhD defense. Next, Yang is headed to John’s Hopkins University where he will work in the lab of Dr. Taekjip Ha, a world leader in the development of single molecule fluorescence microscopy and force spectroscopy.
Yang’s pioneering research wasn’t always smooth sailing. “I didn’t get my first experiment done until the first semester of my third year. Everything before that didn’t work.” He credits his perseverance to his father’s example—“agriculture is even slower, waiting for the growth of plants. You can only do two experiments a year!”—as well as his own scientific curiosity. His advisor, Khalid Salaita, was also an inspiration throughout the process. “He is always passionate and ignited my love for science. You love it and you work hard to make something meaningful to the society and also make yourself valuable, so, that’s what I’d like to do and that’s because of these two people.”
Does all this mean that Yang has overcome his initial reluctance to follow in his father’s footsteps towards biology?
“I think I’m going back to the route, mining chemistry, biology. In the beginning I was against it, but I do like it.” Still, chemistry has his heart. “Chemists not only create new tools, new theories and new materials, but also create new opportunities. And if you want to study biology as a chemist, there are some advantages too because you can understand and explore the secret of life at the molecular level.”
The Weinert Group has research featured in the June issue of Nature Communications. The paper, “An O2-sensing stressosome from a Gram-negative bacterium,” is co-authored by Xin Jia, Jian-bo Wang, Shannon Rivera, Duc Duong, and Emily E. Weinert.
Bacteria have evolved numerous pathways to sense and respond to changing environmental conditions, including, within Gram-positive bacteria, the stressosome complex that regulates transcription of general stress response genes. However, the signalling molecules recognized by Gram-positive stressosomes have yet to be identified, hindering our understanding of the signal transduction mechanism within the complex. Furthermore, an analogous pathway has yet to be described in Gram-negative bacteria. Here we characterize a putative stressosome from the Gram-negative bacterium Vibrio brasiliensis. The sensor protein RsbR binds haem and exhibits ligand-dependent control of the stressosome complex activity. Oxygen binding to the haem decreases activity, while ferrous RsbR results in increased activity, suggesting that the V. brasiliensis stressosome may be activated when the bacterium enters anaerobic growth conditions. The findings provide a model system for investigating ligand-dependent signalling within stressosome complexes, as well as insights into potential pathways controlled by oxygen-dependent signalling within Vibrio species.
Ian Pavelich comes to Emory from the Milwaukee School of Engineering—“it was an extremely difficult four years, but it left me a focused engineer with a unique skill set.” In Milwaukee, Ian also had the opportunity to participate in both educational and scientific research, preparing him to hit the ground running at Emory. Ian identified Emory as his top school early in the application process and felt at home after coming to visit Atlanta. He joined the Emory community this summer, doing research in the Salaita Lab.
“Just to show the dedication I had to moving my life to Atlanta, I drove for 14 straight hours with the help of my partner to manage the move-in just days after I graduated. On top of the 14 hours, I also finished the move-in and unpacked everything once my parents showed up with all the food needed to refuel!”
Division of Interest: Biomolecular
What Ian is Most Looking Forward to at Emory: “Everything! Taking specialized classes, learning to teach, and performing impactful research are all exciting prospects. Furthermore, I’m looking forward to being a part of LGS and the Emory community.”
Ha An Nguyen comes to Emory from the University of Richmond. Originally, she intended to study engineering in college, but sitting in on a philosophy class during a campus visit convinced her that she would benefit from a liberal arts education. Beyond Emory’s liberal arts mission, Ha An was drawn to Emory because of our research strengths and our close-knit community. She says: “I would like to do exciting, interdisciplinary research that will let me learn and master various laboratory techniques and gain a deep understanding of the chemistry behind a cellular process.”
Division of Interest: Biomolecular
What makes Ha An Unique: I was born in India and grew up in Turkey, Vietnam and Pakistan. And I really, really love food!
What Ha An is Most Looking Forward to at Emory: Everything!
Siying Cen comes from Liuzhou, a southern city in China. As a result, she feels comfortable about Atlanta’s weather. Siying Cen gradated from Wuhan University, China. Her research background is in synthesis and analysis, but she is now interested in biophysics. Siying loves singing a lot and want to set up a “chemrus” in the Department of Chemistry.