1887

Chapter 7 : Type III Secretion Systems

MyBook is a cheap paperback edition of the original book and will be sold at uniform, low price.

Ebook: Choose a downloadable PDF or ePub file. Chapter is a downloadable PDF file. File must be downloaded within 48 hours of purchase

Buy this Chapter
Digital (?) $15.00

Preview this chapter:
Zoom in
Zoomout

Type III Secretion Systems, Page 1 of 2

| /docserver/preview/fulltext/10.1128/9781555817893/9781555812454_Chap07-1.gif /docserver/preview/fulltext/10.1128/9781555817893/9781555812454_Chap07-2.gif

Abstract:

Type III secretion system (TTSS) is believed to have originally evolved from the flagellar export system and is now dispersed among a number of both animal- and plant-interacting gram-negative bacteria. The aim of much current research on TTSS is to understand the mechanisms involved in effector secretion/injection and what the effectors are doing inside the host cell. Bacterial pathogens use several different protein secretion pathways to export virulence proteins from the bacterial cytoplasm to their site of action. Chaperones bind to effector proteins in the bacterial cytosol and remain cytosolic following export of their cognate substrate. Secreted proteins exhibiting significant structural similarities to YopB and YopD are present in all TTSSs of animal pathogens but not plant pathogens. Secretion of LcrQ upon cell contact depletes LcrQ from the cytoplasmic compartment and triggers increased transcription of type III genes. Secretion and polymerization of PrgI are required to complete the assembly of the needle complex and type III export apparatus. Two flagellar components, FlhB, an inner membrane protein with a substantial C-terminal cytoplasmic domain, and FliK, the secreted hook-length control protein, are proposed to be involved in switches substrate specificity process. An important question is how far knowledge of flagellar biogenesis can be extrapolated to understand the structure and function of the type III export apparatus. It is obvious that there will be features unique to each system; however, the basic process of transporting substrates across the bacterial membranes appears to be relatively well conserved.

Citation: Plano G, Schesser K, Nilles M. 2003. Type III Secretion Systems, p 95-114. In Burns D, Barbieri J, Iglewski B, Rappuoli R (ed), Bacterial Protein Toxins. ASM Press, Washington, DC. doi: 10.1128/9781555817893.ch7

Key Concept Ranking

Type III Secretion System
0.4334146
Type I Secretion System
0.41325447
0.4334146
Highlighted Text: Show | Hide
Loading full text...

Full text loading...

Figures

Image of Figure 1
Figure 1

Genetic organization of the virulence plasmid pCD1. (A) Genes encoding the components of the TTSS are depicted as arrows showing the direction of transcription. Genes encoding proteins involved in the assembly, regulation, and function of the type III secretion apparatus are arranged in polycistronic operons within an approximately 25-kb region of the plasmid (filled-in arrows), suggesting that they were inherited collectively. In contrast, genes encoding the secreted effector proteins and their chaperones (open arrows) are found in mono- or bicistronic operons scattered around the remainder of the plasmid, suggesting that they were inherited independently. (B) HeLa cells infected with -carrying plasmid pCD1 showing YopE-dependent cytotoxicity (from reference with permission). (C) HeLa cells infected with a strain with a defective TTSS (from reference with permission).

Citation: Plano G, Schesser K, Nilles M. 2003. Type III Secretion Systems, p 95-114. In Burns D, Barbieri J, Iglewski B, Rappuoli R (ed), Bacterial Protein Toxins. ASM Press, Washington, DC. doi: 10.1128/9781555817893.ch7
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 1
Figure 1

Model of a bacterial PAI. The boxes represent genes, the arrows indicate the presence of direct repeats at the ends of the PAI. DR, direct repeats; , integrase gene; , virulence-associated gene; IS, insertion sequence; Δori, pseudo-origin of replication; , transposase gene. At the lower part of the figure, the estimated GC content is indicated.

Citation: Plano G, Schesser K, Nilles M. 2003. Type III Secretion Systems, p 95-114. In Burns D, Barbieri J, Iglewski B, Rappuoli R (ed), Bacterial Protein Toxins. ASM Press, Washington, DC. doi: 10.1128/9781555817893.ch7
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 2
Figure 2

Models for recognition of type III secretion signals. (A) mRNA secretion signal hypothesis. Translation of mRNA is proposed to be inhibited by its own RNA structure or by a component of the type III secretion machinery. The inhibition of translation is relieved upon interaction of the mRNA with the type III secretion apparatus, triggering cotranslational secretion of YopQ. (B) Amino acid secretion signal hypothesis. Translated YopE is recognized by the SycE chaperone, forming a stable cytosolic YopE/SycE complex. Recognition of an N-terminal amino acid sequence by a component of the secretion apparatus triggers YopE secretion and release of SycE.

Citation: Plano G, Schesser K, Nilles M. 2003. Type III Secretion Systems, p 95-114. In Burns D, Barbieri J, Iglewski B, Rappuoli R (ed), Bacterial Protein Toxins. ASM Press, Washington, DC. doi: 10.1128/9781555817893.ch7
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 3
Figure 3

Cell contact-dependent secretion and translocation of Yops. Before contact with a eukaryotic cell, YopN, TyeA, SycN, YscB, and LcrG prevent Yop secretion, possibly by physically blocking the secretion channel. Contact with a eukaryotic cell relieves the block in secretion at the point of cell-to-cell contact. Secreted YopB, YopD, and LcrV assemble into a pore-forming translocon within the eukaryotic membrane, facilitating the translocation of effector proteins into the eukaryotic cell. Secretion of LcrQ, a negative regulatory protein, triggers increased transcription of genes encoding the Yop effector proteins, ensuring the availability of effector proteins for delivery. Once inside the eukaryotic cell, the Yop effector proteins block phagocytosis and subvert the normal signaling pathways of the cell.

Citation: Plano G, Schesser K, Nilles M. 2003. Type III Secretion Systems, p 95-114. In Burns D, Barbieri J, Iglewski B, Rappuoli R (ed), Bacterial Protein Toxins. ASM Press, Washington, DC. doi: 10.1128/9781555817893.ch7
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 4
Figure 4

Hypothetical models of the flagellar and SPI-1 type III secretion machines. The proposed locations of type III secretion components within the flagellar basal body-hook-filament structure (A) and the needle complex structures (B) are shown. The flagellar FliI-FliH ATPase complex may deliver substrates and energize export via an inner membrane secretory complex contained within a patch of membrane within the MS-ring structure. Secreted substrates are delivered into a central channel within the flagellar basal body-hook-filament structure, where they eventually assemble at the distal end of this structure. A similar targeting pathway may function to deliver proteins to the SPI-1 type III secretion apparatus. Effector proteins exported across the inner membrane may enter a channel within the needle complex base and eventually be targeted to the extracellular environment via the needle structure or into a eukaryotic cell with the help of the SipBCD translocon. Electron micrographs of purified SPI-1 needle complexes (C) and surface-localized needle complexes (D) visualized on osmotically shocked bacteria (from reference with permission).

Citation: Plano G, Schesser K, Nilles M. 2003. Type III Secretion Systems, p 95-114. In Burns D, Barbieri J, Iglewski B, Rappuoli R (ed), Bacterial Protein Toxins. ASM Press, Washington, DC. doi: 10.1128/9781555817893.ch7
Permissions and Reprints Request Permissions
Download as Powerpoint

References

/content/book/10.1128/9781555817893.chap7
1. Anderson, D. M.,, and O. Schneewind. 1997. A mRNA signal for the type III secretion of Yop proteins by Yersinia enterocolitica. Science 278:11401143.
2. Kubori, T.,, Y. Matsushima,, D. Nakamura,, J. Uralil,, M. Lara-Tejero,, A. Sukhan,, J. E. Galán,, and S. Aizawa. 1998. Supramolecular structure of the Salmonella typhimurium type III protein secretion system. Science 280:602605.
3. Lloyd, S. A.,, M. Norman,, R. Rosqvist,, and H. Wolf-Watz. 2001. Yersinia YopE is targeted for type III secretion by N-terminal, not mRNA, signals. Mol. Microbiol. 39: 520531.
4. Luo, Y.,, M. G. Bertero,, E. A. Frey,, R. A. Pfuetzner,, M. R. Wenk,, L. Creagh,, S. L. Marcus,, D. Lim,, F. Sicheri,, C. Kay,, C. Haynes,, B. B. Finlay,, and N. C. J. Strynadka. 2001. Structural and biochemical characterization of the type III secretion chaperones CesT and SigE. Nat. Struct. Biol. 8:10311036.
5. Macnab, R. M. 1999. The bacterial flagellum: reversible rotary propellor and type III export apparatus. J. Bacteriol. 181:71497153.
6. Matson, J. S.,, and M. L. Nilles. 2001. LcrG-LcrV interaction is required for control of Yop secretion in Yersinia pestis. J. Bacteriol. 183:50825091.
7. Stebbins, C. E.,, and J. E. Galán. 2001. Maintenance of an unfolded polypeptide by a cognate chaperone in bacterial type III secretion. Nature 414:7781.
1. Cornelis, G. R.,, and F. Van Gijsegem. 2000. Assembly and function of type III secretory systems. Annu. Rev. Microbiol. 54:735774.
2. Galán, J. E. 2001. Salmonella interactions with host cells: type III secretion at work. Annu. Rev. Cell Dev. Biol. 17:5386.
3. Kimbrough, T. G.,, and S. I. Miller. 2001. Assembly of the type III secretion needle complex of Salmonella typhimurium. Microb. Infect. 4:7582.
4. Lloyd, S. A., Å . Forsberg, H. Wolf-Watz, and M. S. Francis. 2001. Targeting exported substrates to the Yersinia TTSS: different functions for different signals. Trends Microbiol. 9:367371.

Tables

Generic image for table
Table 1

Bacterial virulence-associated type III secretion systems

Citation: Plano G, Schesser K, Nilles M. 2003. Type III Secretion Systems, p 95-114. In Burns D, Barbieri J, Iglewski B, Rappuoli R (ed), Bacterial Protein Toxins. ASM Press, Washington, DC. doi: 10.1128/9781555817893.ch7
Generic image for table
Table 2

Secreted proteins required for translocation of effector proteins into eukaryotic cells

Citation: Plano G, Schesser K, Nilles M. 2003. Type III Secretion Systems, p 95-114. In Burns D, Barbieri J, Iglewski B, Rappuoli R (ed), Bacterial Protein Toxins. ASM Press, Washington, DC. doi: 10.1128/9781555817893.ch7
Generic image for table
Table 3

Broadly conserved and system-specific type III secretion components

Citation: Plano G, Schesser K, Nilles M. 2003. Type III Secretion Systems, p 95-114. In Burns D, Barbieri J, Iglewski B, Rappuoli R (ed), Bacterial Protein Toxins. ASM Press, Washington, DC. doi: 10.1128/9781555817893.ch7

This is a required field
Please enter a valid email address
Please check the format of the address you have entered.
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error