Carbapenem-Resistant enterobacterales — Image Credit: sokolova_sv/Shutterstock

May 25, 2023
Rima Mycynek

Massachusetts General Hospital’s Roby Bhattacharyya, MD, PhD, presented today on “Transcriptional Profiling for Infectious Disease Diagnostics and Discovery” for the Levy CIMAR’s May 25th Science Lunch, our last seminar of the ’22-’23 season. Dr. Bhattacharyya is an Assistant Professor in the Infectious Diseases Division at MGH as well as an Associate Member of the Broad Institute and an Assistant Professor at Harvard Medical School.

Dr. Bhattacharyya maintains a lab at the Broad where he and his team pursue basic and translational research on pathogenic microbes, with a particular focus on antimicrobial resistance and transcriptional responses to antibiotic exposure, and on characterizing their impact on infected patients, including the immune responses elicited upon systemic infection such as sepsis or COVID-19.

For today’s seminar, Dr. Bhattacharyya focused mainly on resistance to carbapenems. Based on a series of observations from the MGH Clinical Microbiology lab and some Bhattacharyya Lab transcriptional experiments, Dr. Bhattacharyya and team are taking a fresh look at a long-described issue in beta-lactam resistance, that of the “inoculum effect,” which essentially means that the more cells you treat with beta-lactams, the more antibiotic it takes to kill them.

Dr. Bhattacharyya describes the lab’s current research on this topic as follows: “We are exploring both the mechanistic basis for this phenomenon (is it simply due to secreted enzymes building up in solution, a form of cooperativity between cells at high density? or is there more to it?) and its clinical consequences (strains with the capacity for high-level resistance may ‘fool’ standard assays done at lower inocula) using carbapenems as a model beta-lactam, given the clinical importance of this ultra-broad-spectrum antibiotic.” (source) You can learn more about Dr. Bhattacharyya and the Bhattacharyya Lab’s work at https://www.bhattacharyyalab.org.

Video: Transcriptional Profiling for Infectious Disease Diagnostics and Discovery – Massachusetts General Hospital’s Roby Bhattacharyya, MD, PhD