Mariana Castanheira

Experience

Dr. Mariana Castanheira has spent nearly two decades at JMI Laboratories, part of Element Materials Technology and operating as Element Iowa City, advancing through roles of increasing scientific leadership. Beginning as a Research Scientist in 2007, she progressed through Associate Director and Director of Molecular and Microbiology, served as Chief Operations Officer, and has held the role of Chief Scientific Officer since 2020. In this capacity, she is responsible for designing and overseeing antimicrobial and antifungal drug development projects, surveillance studies, and molecular projects that characterize resistance mechanisms across the laboratory’s global client base.

Prior to joining the laboratory, Dr. Castanheira completed a post-doctoral fellowship at UNIFESP and a nine-month research position at QIAGEN, experiences that deepened her foundational expertise in molecular microbiology and resistance mechanisms. Her scientific grounding in beta-lactamases,  gram-positive and -negative bacterial resistance – established during her doctoral training and extended through additional training at the Department of Pathology and Microbiology at the University of Bristol (UK) – has informed more than 15 years of discovering and characterizing resistance genes and mechanisms.

Career Highlights

Dr. Castanheira is the leading author on over 100 peer-reviewed publications and presents annually at major international conferences, including ESCMID Global, where her team delivered 22 presentations in 2026. Her research has directly shaped clinical practice: more than 50 publications from the Element Iowa City group were cited in the 2024 IDSA Guidance on the Treatment of Antimicrobial Resistant Gram-Negative Infections, reflecting the real-world impact of the laboratory’s surveillance and resistance characterization work.

She maintains a global network of research collaborators spanning pharmaceutical partners, academic institutions, and medical centers, and has served on the program committees of major international conferences in microbiology and drug development. Dr. Castanheira is an active advisor to the Clinical and Laboratory Standards Institute (CLSI) Subcommittees for Antimicrobial and Antifungal Susceptibility Testing, contributing to the standards that laboratories worldwide rely on for resistance breakpoint determinations.