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Updated: Jan 28, 2026

Author Spotlight: Advancing Antibiotic Resistance Research Using an Efflux-Deficient Bacterial Strain and a Single-Copy Gene Expression System
Published on: January 5, 2024
Recent paradigm shift in the assembly of bacterial tripartite efflux pumps and the type I secretion system
Inseong Jo1, Jin-Sik Kim2, Yongbin Xu3
1Department of Agricultural Biotechnology, Center for Food Safety and Toxicology, Center for Food and Bioconvergence, Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
Abstract:
Tripartite efflux pumps and the type I secretion system of Gram-negative bacteria are large protein complexes that span the entire cell envelope. These complexes expel antibiotics and other toxic substances or transport protein toxins from bacterial cells. Elucidating the binary and ternary complex structures at an atomic resolution are crucial to understanding the assembly and working mechanism. Recent advances in cryoelectron microscopy along with the construction of chimeric proteins drastically shifted the assembly models. In this review, we describe the current assembly models from a historical perspective and emphasize the common assembly mechanism for the assembly of diverse tripartite pumps and type I secretion systems.
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