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About the Division

Mission

Serve a multipurpose function including evaluating the impact of antimicrobial agents, food contaminants, food additives, nanomaterials, and FDA-regulated products on the microbiome; developing methods to detect and characterize microbial contaminants; determining antimicrobial resistance and virulence mechanisms; conducting research to aid FDA in the areas of women's health, tobacco products, and nanotechnology; and improving risk assessments.

FDA Grand Rounds: The Plasmid Puzzle—Finding Solutions in Salmonella
Presented by Kristina Feye, Ph.D.

Watch the Recorded Presentation

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2023 Select Accomplishments

Developing a Plasmid Analyses Toolbox

NCTR collaborated with CVM scientists to develop tools and approaches to cure bacterial plasmids—genetic structures outside of the bacteria’s chromosome that often carry genes encoding for AMR and/or virulence traits—and specifically remove plasmid genes to identify their functions related to virulence and AMR.

These efforts will help researchers better understand the factors that increase the ability of resistance plasmids to be shared among bacteria spreading AMR. Recent publications describing this work are available in the journals, BMC Genomics, Front Microbiol, and Microbiology Spectrum.

Using Biofilm Models to Study AMR

Biofilm-associated infections associated with implanted medical devices is a major challenge and public health concern. During treatment, bacterial cells in biofilms may be exposed to sublethal concentrations of the antimicrobial agents which can drive antimicrobial resistance development. These studies demonstrate that global protein expression differences within biofilms following antibiotic pressure may improve our understanding of the mechanisms of antibiotic resistance in biofilms. A recent publication describing this work is available in the journal, Pathogens.

Surveying Microbial Contaminants in Commercial Tattoo Inks and Other Related Products

Tattooing and the use of permanent makeup inks have dramatically increased over the last decade. It is estimated that between 20-30% of the U.S. population have at least one tattoo. The process of tattooing involves the injection of different inks into the skin, thereby breaking the epithelial layer that serves as a protection from infection. If inks used for tattooing contain microorganisms, there is the chance for infections to develop. This research found that microbial contamination in commercial tattoo inks and related products is not rare and might be potential sources of human infections, presenting a significant public health concern. With the growing tattoo industry and the global supply chains for tattoo inks, a deep understanding of the microbial contamination in these products is important. A recent publication describing this work is available in the journal, Front Public Health.

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Resources for You

• Division of Microbiology Fact Sheet
• NCTR Grand Rounds: "The Plasmid Puzzle—Finding Solutions in Salmonella" (Presentation recorded in Zoom on July 13, 2023)
• NCTR Grand Rounds: "Studies of SARS-CoV-2 NSP₁ and Envelope Protein" (Presentation recorded in Adobe Connect on March 11, 2021)
• Annual Report
• Meet the Principal Investigators
• About the National Center for Toxicological Research

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