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David Thanassi

By Daniel Dunaief

The American Society for Microbiology named Stony Brook University’s Department of Microbiology and Immunology a “Milestone” program on Oct. 17th, recognizing the department’s historical research contributions in fields ranging from Lyme disease to polio virus, and infection and vaccines.

Stony Brook is the 20th program to receive this distinction from the ASM, joining Cold Spring Harbor Laboratory as the second such distinguished program on Long Island, and the fourth in the state.

It’s a “shared distinction among all the friends and colleagues from the department over the years” since its inception in 1972, said Carol Carter, Distinguished Professor in the department, and recent inductee into the National Academy of Sciences.

“It’s a family-community [honor],” she continued.

The Milestone recognition from the ASM raises the profile of the department and the university, as it recognizes its historical contribution to the field, and encourages and inspires the growing staff in a department in which basic research can lead to breakthrough discoveries.

“This is not an award or discovery for the last year or year before,” said Kevin Gardner, Vice President for Research and member of the Office of the President. “This is for historical levels of achievement over a really long period of time.”

Gardner planned to join department members, politicians including Assemblymember Edward Flood (R-Port Jefferson) and executives at ASM, as part of the recognition ceremony. The ASM, which was founded in 1899, and has over 32,000 members, is a “high-quality professional society and is about as good as they get,” Gardner added.

“It’s a tremendous honor.”

Theresa Koehler, president of ASM, will give a speech on the historic microbial science accomplishments at Stony Brook and designate the site officially a Milestone program.

Professor Emeritus, Nassau Community College/ University Medical Center and ASM Member, Lorraine Findlay, will also attend.

The ASM has been recognizing Milestones in Microbiology sites since 2002, when the first such honoree, Selman Waksam’s Laboratory at Rutgers University, received the honor.

“The program celebrates groundbreaking achievements that have shaped our understanding of microbiology and inspire future generations,” ASM Archivist Colleen Puterbaugh explained in an email.

The Stony Brook Department of Microbiology and Immunology has made the kind of fundamental discoveries regarding how cells work and how DNA and RNA and the different genetic building blocks come together that have led to treatments for diseases like polio, Gardner added.

“These types of recognition really help put the word out about what we’ve done and continue to do,” said David Thanassi, Chair of the Department of Microbiology and Immunology. “It helps build morale” and aids in recruiting additional faculty.

Last year, the department added four faculty members and is in the process of searching for another person to join.

In the wake of the COVID Pandemic, universities and research facilities have emphasized the importance of microbiology, immunology and virology, which are fields that could help provide the kind of basic science that leads to early diagnosis, prevention, and treatment.

“Other places want virologists, too, because there’s a greater awareness of the need for these types of researchers,” said Thanassi.

Compelling research

In the application Carter helped prepare to submit to the ASM, she focused on three specific basic research achievements that have had an important impact on human health.

Joseph Kates, Founding Chair of the department, discovered that viruses could package enzymes required to copy themselves. His research made it possible to target viral polymerases as a type of therapy.

“Up to that point, it really wasn’t known about the basics of how viruses replicate themselves,” said Carter. “Finding this enzyme that viruses have to carry in their coat meant humans could devise a strategy for countering their ability to replicate.”

When she was considering joining the young state university, Carter interviewed with Kates in 1975. Kates “was so impressive and so much fun,” said Carter, “it was difficult to envision why you wouldn’t come and work in his department.”

Additionally, the ASM considered the research of Jorge Benach, Willy Burgdorfer and scientists from the Rocky Mountain Laboratory, who identified the cause of Lyme disease, which is a particular problem on Long Island.

This work made it possible to create antibiotic therapies.

Benach was able to “isolate the spirochetes from patients and demonstrate that they were the causative agent of Lyme,” said Carter.

Benach also characterized the form of the infection that occurs in dogs. Meanwhile, Eckard Wimmer was the first to describe the chemical synthesis of a polio virus without using a natural template. He was also the co-discoverer, with Vincent Racaniello, of the human receptor for poliovirus.

Wimmer’s work started efforts to synthesize organisms in the absence of a natural template, making it possible to develop new strategies in virus vaccine development.

Two plaques

As a part of the ceremony, the ASM will award Stony Brook two plaques. One of them will be visible in the department itself, while the other will go up in the Renaissance School of Medicine’s lobby, near the dean’s office and the library.

Carter suggested that the department continues to conduct research that is globally important.

“These days, the [discoveries] are not low-hanging fruit,” Carter said.

“The answers don’t come easily. You do feel gratified, whether you or somebody else in your unit, provides some sort of understanding that we didn’t appreciate before,” she continued.

In addition to the principal investigators who conducted research that proved important for human health, Carter added that the students who gained experience and insights at the university have gone on to develop productive careers.

“We have had fabulous students.”

Carol A. Carter, PhD, SUNY Distinguished Professor, elected to the National Academy of Sciences. Photo from SBU

Distinguished Professor has a long history of accomplishments in antiviral drug research

Carol A. Carter, PhD, SUNY Distinguished Professor in the Department of Microbiology and Immunology at the Stony Brook University Renaissance School of Medicine (RSOM), was elected as a member to the U.S. National Academy of Sciences (NAS), a society made up of the country’s leading researchers.

According to NAS, members are elected to the National Academy of Sciences in recognition of their distinguished and continuing achievements in original research. Election to the National Academy of Sciences is considered one of the highest honors that a scientist can receive.

Carter is the eighteenth faculty member at Stony Brook University elected to the NAS. She is only the second elected member from the RSOM. World-renowned virologist and Emeritus Professor in the Department of Microbiology and Immunology Eckard Wimmer was elected in 2012.

“Carol has been active in translational research and has exploited her discoveries for the identification of new antiviral compounds,” says David Thanassi, PhD, Professor and Zhang Family Endowed Chair of the Department of Microbiology and Immunology. “Her research illustrates the power of basic science to lead to unexpected insights and generate new avenues for therapeutic development.”

At the NAS Annual Meeting on April 30, 120 new members were elected. This brings the total number of NAS members to 2,617 since the society’s inception in 1863. Members are elected by their peers for their outstanding research. Approximately 500 NAS members have earned a Nobel Prize.

“Frankly speaking, I’m stunned, thrilled and honored to be joining the company of those I have admired throughout my career,” says Carter. “This recognition from the Academy opens the door to the possibility of shining more light on feasible ways to approach targeting non-traditional cellular systems for drug discovery, systems that have long been exploited by viral pathogens for their production,” adds Carter, also an Adjunct Professor in the Department of Physiology & Biophysics within the RSOM, and a Fellow of the American Academy of Microbiology.

Carter is best known as an early pioneer in HIV research. At the onset of the AIDS pandemic, she advanced understanding of the viral-encoded protease and purified the viral capsid protein for structural and biochemical studies. She has also conducted research on Epstein-Barr Virus (EBV) and Severe Acute Respiratory Syndrome Coronavirus Virus-2 (SARS CoV-2), pathogens causing organ transplant rejection and COVID-19, respectively.

In 2001, her groundbreaking research, published in PNAS, identified an interaction between HIV and a host protein (Tsg101) that is essential for the assembly and budding of HIV viral particles from infected cells. Her findings opened a new field of research on host factors in microbial pathogenesis and suggested the possibility of targeting host proteins for developing antimicrobial therapeutics, with implications beyond HIV.

A resident of Stony Brook, Carter has also served as a member of the National Institute of Allergy and Infectious Diseases Advisory Council from 2007 to 2011. She received the Stony Brook University Presidential Award for Promoting Diversity and Academic Excellence in 2013, and the Suffolk County, N.Y., Martin Luther King Jr Commission Public Service Award in 2016.

Currently, she collaborates with Cold Spring Harbor Laboratory DNA Learning Center staff and Stony Brook Faculty in the RSOM, the School of Marine and Atmospheric Sciences, School of Health Professions, and the Office of Undergraduate Admissions, in efforts to mentor high school students interested in pursuing careers in health sciences professions.

She continues her research focus on several areas, including the role of cellular proteins in assembly of HIV and other members of the Retrovirus family; Tsg101 structure/function analysis; and antiviral drug development, to name a few.

Carol A. Carter received her PhD from Yale University in 1972. She has been a faculty member at Stony Brook University since 1975.

 

David Thanassi. Photo by Jeanne Neville
*Please note: This article was updated on Oct. 15 to include a reference to former President Bill Clinton (D) in the fifth paragraph.

By Daniel Dunaief

David Thanassi wants to give dangerous bacteria in the kidney a haircut.

No, not exactly, but Thanassi, Zhang Family Professor and Chair of the Department of Microbiology and Immunology at the Renaissance School of Medicine at Stony Brook University, has studied how hair-like structures called P pili in the bacteria Escherichia coli are assembled on the bacterial surface. 

These pili allow bacteria to hang on to the walls of the kidney, where urine would otherwise flush them out.

Learning about pili at different stages of development could provide a way to keep them from attaching themselves to the kidney and from entering the bloodstream, which could lead to the potentially lethal problem of bacterial sepsis. Indeed, this week, former President Bill Clinton (D) checked into the intensive care unit at the University of California Irvine Medical Center after a urinary tract infection spread to his bloodstream.

“We have been looking at this as a really important aspect of initiating infection from a bacteria’s point of view,” Thanassi said. “How do they build these structures” that lead to infection and illness?

Recently, Thanassi published the structure of these pili in the journal Nature Communication.

The current work builds on previous efforts from Thanassi to determine the structure of these pili in the bladder. He has been exploring how the thousands of proteins that make up the pili get transported and assembled in the correct order. “If we can understand that aspect, we can disrupt their assembly or function,” he said.

Urinary tract infections are a major infectious disease, particularly for women. Indeed, about half of all women will have at least one urinary tract infection, which can be uncomfortable and can require some form of medication. 

In some cases, the infections can be recurrent, leading to frequent infections and the repeated need for antibiotics.

The bacteria that cause these infections can become resistant to antibiotics, increasing the importance of finding alternative approaches to these infections, such as interfering with pili.

To be sure, the solution to reducing the bacteria’s ability to colonize the kidney or urinary tract would likely require other steps, as these invaders have additional ways beyond the pili to colonize these organs. Nonetheless, disrupting the way they adhere to the kidney could be a constructive advance that could lead to improved infection prevention and treatment.

One likely strategy could involve using an anti-pilus treatment in combination with other antibiotics, Thanassi explained.

For people who have recurrent infections, anti-pilus therapeutics could offer a solution without resorting to long-term antibiotics.

In his lab, Thanassi is interested in small molecules or chemicals that would disrupt the early stage in pili assembly. “We think of these as protein-protein interactions that are required to build these” pili, he said.

By using a fluorescence reporter, Thanassi and his colleagues can screen libraries of chemicals to determine what might inhibit the process.

As with many biological systems, numerous compounds may seem appropriate for the job, but might not work, as medicine often requires a specific molecule that functions within the context of the dynamic of a living system.

For the helpful bacteria in the gut, pili are not as important as they are for the harmful ones in the kidney, which could mean that an approach that blocked the formation of these structures may not have the same intestinal and stomach side effects as some antibiotics.

To determine the way these pili develop structurally, Thanassi and his lab used molecular and biochemical techniques to stop the assembly of pili at specific stages.

Bacteria assemble these pili during the course of about 30 minutes. An usher proteins serves as the pilus assembly site and pilus secretion channel in the bacterial outer membrane. The usher acts as a nanomachine, putting the pilus proteins into their proper order. A chaperone protein brings the pilus subunits to the usher protein.

In their development, the pili require a protein channel, which is an assembly site.

Thanassi started by working on the usher protein in isolation. The usher proteins function to assemble the thousands of pilus subunits that make up each pilus fiber. The process also involves chaperone proteins, which bind to nascent subunit proteins and help the subunits fold. The chaperone then delivers the subunit proteins to the usher for assembly into the pilus fiber. He used molecular and biochemical methods to express and purify the usher protein.

The assembly process involves interactions between chaperone-subunit complexes and the usher. Over the years, Thanassi has determined how the different proteins work together to build and secrete a pilus.

He was able to force the bacteria to express only one version of the assembly step and then isolate that developmental process.

The majority of the pilus is like a spring or a coil, which can stretch and become longer and straighter to act as a shock absorber, allowing the bacteria to grab on to the kidney cells rather than breaking.

Other researchers are studying how they might make the pili more brittle, preventing that spring-like action from working and compromising its ability to function.

“We’re trying to prevent the pili from assembling in the first place,” Thanassi explained. “Our approach is to try and get molecules that prevent the interaction from occurring.” He is looking at the specific function of one molecule that prevents the usher assembly platform from developing properly, which would wipe out the assembly site.

Thanassi credits former Stony Brook Professor Huilin Li, who is now Chair in the Department of Structural Biology at the Van Andel Institute in Grand Rapids, Michigan, with providing structural insights from his work with the cryo-electron microscoipe. The technology has “revolutionized the work we do,” said Thanassi.

Residents of Smithtown, Thanassi and his wife Kate Kaming, who is Senior Director of Cancer Development at Northwell Health Foundation, have two children. Joseph, 22, attends Northeastern University. Miles, 20, is studying at the Massachusetts Institute of Technology.

Thanassi grew up in South Burlington, Vermont and is an avid skier. He also enjoys mountain biking, walking and music.

Thanassi hopes this latest structural work may one day offer help either with the prevention of infections or with their treatment.