Autotransporter and Two-Partner Secretion: Delivery of Large-Size Virulence Factors by Gram-Negative Bacterial Pathogens

Abstract

A number of protein secretion mechanisms have been identified in gram-negative pathogens. Many of these secretion systems are dependent upon the Sec translocase for protein export from the cytoplasm into the periplasm and then utilize other mechanisms for transport from the periplasm through the outer membrane. In this article, we review secretion similarities between autotransporter and two-partner secretion systems, and we report similarities between the autotransporter secretion mechanism with that of intimin/invasins. Considering that many secreted proteins are virulence factors, a better understanding of their secretion mechanisms will aid in the development of disease treatments and new bacterial vaccines.

Keywords :

• Protein Secretion
• Gram-Negative Bacteria
• Autotransporter
• Two-Partner Secretion
• Invasin

ACKNOWLEDGMENTS

We would like to thank Dr. Rachel Fernandez and Maria Kostakioti for critical review of this manuscript and Robert Bradley for his aid in generating the figures within this work. This project has been funded by research grants from NIH, USDA, and the Welch Foundation (E-1548).