Expression and Secretion Hierarchy in the Nonflagellar Type III Secretion System

Abstract

Type III secretion systems that deliver bacterial proteins into eukaryotic cells are the basis for both symbiotic and pathogenic relationships between many Gram-negative bacteria and their hosts. Exploration of the structure, function and assembly of this secretion system has greatly enhanced our knowledge of bacterial ecology in the context of infectious disease and has spawned new avenues in anti-infective research with a view towards inhibiting virulence functions. We outline advances in understanding type III secretion system function with specific focus on how assembly is hierarchically coordinated at the level of expression and how the type III secretion system mediates transitions in substrate specificity.

Keywords:

• assembly
• hierarchy
• regulation
• type III secretion

Financial & competing interests disclosure

Work on type III secretion and regulatory hierarchy in the Coombes laboratory is supported by operating grants from the Canadian Institutes of Health Research (MOP-82704), the Natural Sciences and Engineering Research Council of Canada (341435–2010) and Boehringer Ingelheim Canada. Suzanne E Osborne is the recipient of the CIHR-Vanier Canada Graduate Scholarship. Brian K Coombes is a CIHR New Investigator and the recipient of the Early Researcher Award from the Ontario Ministry of Research and Innovation Infrastructure support in the Coombes laboratory was provided by the Canada Foundation for Innovation Leaders Opportunity Fund. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Additional information

Funding

Work on type III secretion and regulatory hierarchy in the Coombes laboratory is supported by operating grants from the Canadian Institutes of Health Research (MOP-82704), the Natural Sciences and Engineering Research Council of Canada (341435–2010) and Boehringer Ingelheim Canada. Suzanne E Osborne is the recipient of the CIHR-Vanier Canada Graduate Scholarship. Brian K Coombes is a CIHR New Investigator and the recipient of the Early Researcher Award from the Ontario Ministry of Research and Innovation Infrastructure support in the Coombes laboratory was provided by the Canada Foundation for Innovation Leaders Opportunity Fund. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.