Engineering a Tagged sctJ Fusion Protein to Visualize Type III Secretion System Dynamics in Chlamydia Trachomatis
Faculty Mentor Information
Dr. Scott Grieshaber, University of Idaho
Presentation Date
7-15-2026
Abstract
Chlamydia trachomatis is an obligate intracellular pathogen that undergoes a biphasic developmental cycle consisting of infectious elementary bodies and replicative reticulate bodies. The type III secretion system (T3SS) is essential for host-cell interactions and bacterial development, but the timing and localization of T3SS components throughout the developmental cycle remain incompletely understood. This project aims to engineer the C. trachomatis chromosome to generate a detectable SctJ fusion protein by introducing an epitope-based FLAG tag in-frame with the sctJ gene. Using CRISPR-based genome engineering, PCR cloning, and recombineering approaches, genetic constructs have been designed and assembled for targeted chromosomal modification. This tagged strain will enable direct detection and localization of SctJ expression during different developmental stages, providing insight into T3SS regulation and its role in chlamydial development and host-pathogen interactions.
Engineering a Tagged sctJ Fusion Protein to Visualize Type III Secretion System Dynamics in Chlamydia Trachomatis
Chlamydia trachomatis is an obligate intracellular pathogen that undergoes a biphasic developmental cycle consisting of infectious elementary bodies and replicative reticulate bodies. The type III secretion system (T3SS) is essential for host-cell interactions and bacterial development, but the timing and localization of T3SS components throughout the developmental cycle remain incompletely understood. This project aims to engineer the C. trachomatis chromosome to generate a detectable SctJ fusion protein by introducing an epitope-based FLAG tag in-frame with the sctJ gene. Using CRISPR-based genome engineering, PCR cloning, and recombineering approaches, genetic constructs have been designed and assembled for targeted chromosomal modification. This tagged strain will enable direct detection and localization of SctJ expression during different developmental stages, providing insight into T3SS regulation and its role in chlamydial development and host-pathogen interactions.