scholarly journals P orphyromonas gingivalis and related bacteria: from colonial pigmentation to the type IX secretion system and gliding motility

2014 ◽  
Vol 50 (1) ◽  
pp. 1-8 ◽  
Author(s):  
K. Nakayama
Keyword(s):  
Secretion System ◽  
Gliding Motility ◽  
Type Ix Secretion System

scholarly journals The Carboxy-Terminal Region ofFlavobacterium johnsoniaeSprB Facilitates Its Secretion by the Type IX Secretion System and Propulsion by the Gliding Motility Machinery

2019 ◽  
Vol 201 (19) ◽  
Author(s):  
Surashree S. Kulkarni ◽  
Joseph J. Johnston ◽  
Yongtao Zhu ◽  
Zachary T. Hying ◽  
Mark J. McBride
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Cell Surface ◽  
Type A ◽  
Secretion System ◽  
Gliding Motility ◽  
Foreign Protein ◽  
Type B ◽  
Content Type ◽  
Type Ix Secretion System

ABSTRACTFlavobacterium johnsoniaeSprB moves rapidly along the cell surface, resulting in gliding motility. SprB secretion requires the type IX secretion system (T9SS). Proteins secreted by the T9SS typically have conserved C-terminal domains (CTDs) belonging to the type A CTD or type B CTD family. Attachment of 70- to 100-amino-acid type A CTDs to a foreign protein allows its secretion. Type B CTDs are common but have received little attention. Secretion of the foreign protein superfolder green fluorescent protein (sfGFP) fused to regions spanning the SprB type B CTD (sfGFP-CTDSprB) was analyzed. CTDs of 218 amino acids or longer resulted in secretion of sfGFP, whereas a 149-amino-acid region did not. Some sfGFP was secreted in soluble form, whereas the rest was attached on the cell surface. Surface-attached sfGFP was rapidly propelled along the cell, suggesting productive interaction with the motility machinery. This did not result in rapid cell movement, which apparently requires additional regions of SprB. Secretion of sfGFP-CTDSprBrequired coexpression withsprF, which lies downstream ofsprB. SprF is similar in sequence toPorphyromonas gingivalisPorP. MostF. johnsoniaegenes encoding proteins with type B CTDs lie immediately upstream ofporP/sprF-like genes. sfGFP was fused to the type B CTD from one such protein (Fjoh_3952). This resulted in secretion of sfGFP only when it was coexpressed with its cognate PorP/SprF-like protein. These results highlight the need for extended regions of type B CTDs and for coexpression with the appropriate PorP/SprF-like protein for efficient secretion and cell surface localization of cargo proteins.IMPORTANCETheF. johnsoniaegliding motility adhesin SprB is delivered to the cell surface by the type IX secretion system (T9SS) and is rapidly propelled along the cell by the motility machinery. How this 6,497-amino-acid protein interacts with the secretion and motility machines is not known. Fusion of the C-terminal 218 amino acids of SprB to a foreign cargo protein resulted in its secretion, attachment to the cell surface, and rapid movement by the motility machinery. Efficient secretion of SprB required coexpression with the outer membrane protein SprF. Secreted proteins that have sequence similarity to SprB in their C-terminal regions are common in the phylumBacteroidetesand may have roles in adhesion, motility, and virulence.

scholarly journals Bacteriophage Resistance Affects Flavobacterium columnare Virulence Partly via Mutations in Genes Related to Gliding Motility and Type IX Secretion System

2020 ◽  
Author(s):  
Heidi M. T. Kunttu ◽  
Anniina Runtuvuori-Salmela ◽  
Krister Sundell ◽  
Tom Wiklund ◽  
Mathias Middelboe ◽  
...  
Keyword(s):  
Phage Therapy ◽  
Secretion System ◽  
Gliding Motility ◽  
Genetic Mutations ◽  
Phage Resistance ◽  
Flavobacterium Columnare ◽  
Aquaculture Industry ◽  
Columnaris Disease ◽  
Phage Sensitivity ◽  
Type Ix Secretion System

AbstractIncreasing problems with antibiotic resistance has directed interest towards phages as tools to treat bacterial infections in the aquaculture industry. However, phage resistance evolves rapidly in bacteria posing a challenge for successful phage therapy. To investigate phage resistance in the fish pathogenic bacterium Flavobacterium columnare, two phage-sensitive, virulent wild-type isolates, FCO-F2 and FCO-F9, were exposed to phages and subsequently analyzed for bacterial viability and colony morphology. Twenty-four phage-exposed isolates were further characterized for phage resistance, antibiotic susceptibility, motility, adhesion and biofilm formation on polystyrene surface, protease activity, whole genome sequencing and virulence against rainbow trout fry. Bacterial viability first decreased in the exposure cultures, subsequently increasing after 1-2 days. Simultaneously, the colony morphology of the phage-exposed isolates changed from original rhizoid to rough. The rough isolates arising in phage exposure were phage-resistant with low virulence, whereas rhizoid isolates maintained phage sensitivity, though reduced, and high virulence. Gliding motility and protease activity were also related to the phage sensitivity. Observed genetic mutations in phage-resistant isolates were mostly located in genes coding for type IX secretion system, a component of the flavobacterial gliding motility machinery. However, there were mutational differences between individual isolates, and not all phage-resistant isolates had genetic mutations. This indicates that development of phage resistance in F. columnare probably is a multifactorial process including both genetic mutations and changes in gene expression. Phage resistance may not, however, be a challenge for development of phage therapy against F. columnare infections, since phage resistance is associated with decrease in bacterial virulence.ImportancePhage resistance of infectious bacteria is a common phenomenon posing challenges for development of phage therapy. Along with growing World population and need for increased food production, constantly intensifying animal farming has to face increasing problems of infectious diseases. Columnaris disease, caused by F. columnare, is a worldwide threat for salmonid fry and juvenile farming. Without antibiotic treatments, infections can lead to 100% mortality in a fish stock. Phage therapy of columnaris disease would reduce a development of antibiotic-resistant bacteria and antibiotic loads by the aquaculture industry, but phage-resistant bacterial isolates may become a risk. However, phenotypic and genetic characterization of phage-resistant F. columnare isolates in this study revealed that they are less virulent than phage-sensitive isolates and thus not a challenge for phage therapy against columnaris disease. This is a valuable information for the fish farming industry globally when considering phage-based prevention and curing methods for F. columnare infections.

scholarly journals The Type IX Secretion System: Advances in Structure, Function and Organisation

2020 ◽  
Vol 8 (8) ◽  
pp. 1173 ◽  
Author(s):  
Dhana G. Gorasia ◽  
Paul D. Veith ◽  
Eric C. Reynolds
Keyword(s):  
Cell Surface ◽  
Structure Function ◽  
Secretion System ◽  
Gliding Motility ◽  
Flavobacterium Johnsoniae ◽  
Bacteroidetes Phylum ◽  
Transcription Regulators ◽  
Type Ix Secretion System ◽  
Insight Into ◽  
Made In

The type IX secretion system (T9SS) is specific to the Bacteroidetes phylum. Porphyromonas gingivalis, a keystone pathogen for periodontitis, utilises the T9SS to transport many proteins—including its gingipain virulence factors—across the outer membrane and attach them to the cell surface. Additionally, the T9SS is also required for gliding motility in motile organisms, such as Flavobacterium johnsoniae. At least nineteen proteins have been identified as components of the T9SS, including the three transcription regulators, PorX, PorY and SigP. Although the components are known, the overall organisation and the molecular mechanism of how the T9SS operates is largely unknown. This review focusses on the recent advances made in the structure, function, and organisation of the T9SS machinery to provide further insight into this highly novel secretion system.

Type IX secretion system effectors and virulence of the model Flavobacterium columnare strain MS-FC-4

2021 ◽  
Author(s):  
Nicole C. Thunes ◽  
Rachel A. Conrad ◽  
Haitham H. Mohammed ◽  
Yongtao Zhu ◽  
Paul Barbier ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Virulence Factors ◽  
Genetic Manipulation ◽  
Secretion System ◽  
Gliding Motility ◽  
Secreted Proteins ◽  
Flavobacterium Columnare ◽  
Genes Encoding ◽  
Columnaris Disease ◽  
Type Ix Secretion System

Flavobacterium columnare causes columnaris disease in wild and cultured freshwater fish and is a major problem for sustainable aquaculture worldwide. The F. columnare type IX secretion system (T9SS) secretes many proteins and is required for virulence. The T9SS component GldN is required for secretion and for gliding motility over surfaces. Genetic manipulation of F. columnare is inefficient, which has impeded identification of secreted proteins that are critical for virulence. Here we identified a virulent wild-type F. columnare strain (MS-FC-4) that is highly amenable to genetic manipulation. This facilitated isolation and characterization of two deletion mutants lacking core components of the T9SS. Deletion of gldN disrupted protein secretion and gliding motility and eliminated virulence in zebrafish and rainbow trout. Deletion of porV disrupted secretion and virulence but not motility. Both mutants exhibited decreased extracellular proteolytic, hemolytic, and chondroitin sulfate lyase activities. They also exhibited decreased biofilm formation and decreased attachment to fish fins and to other surfaces. Using genomic and proteomic approaches, we identified proteins secreted by the T9SS. We deleted ten genes encoding secreted proteins and characterized the virulence of mutants lacking individual or multiple secreted proteins. A mutant lacking two genes encoding predicted peptidases exhibited reduced virulence in rainbow trout, and mutants lacking a predicted cytolysin showed reduced virulence in zebrafish and rainbow trout. The results establish F. columnare strain MS-FC-4 as a genetically amenable model to identify virulence factors. This may aid development of measures to control columnaris disease and impact fish health and sustainable aquaculture. IMPORTANCE: Flavobacterium columnare causes columnaris disease in wild and aquaculture-reared freshwater fish and is a major problem for aquaculture. Little is known regarding the virulence factors involved in this disease and control measures are inadequate. The type IX secretion system (T9SS) secretes many proteins and is required for virulence, but the secreted virulence factors are not known. We identified a strain of F. columnare (MS-FC-4) that is well suited for genetic manipulation. The components of the T9SS and the proteins secreted by this system were identified. Deletion of core T9SS genes eliminated virulence. Genes encoding ten secreted proteins were deleted. Deletion of two peptidase-encoding genes resulted in decreased virulence in rainbow trout, and deletion of a cytolysin-encoding gene resulted in decreased virulence in rainbow trout and zebrafish. Secreted peptidases and cytolysins are likely virulence factors and are targets for the development of control measures.

scholarly journals Flavobacterium johnsoniae PorV Is Required for Secretion of a Subset of Proteins Targeted to the Type IX Secretion System

2014 ◽  
Vol 197 (1) ◽  
pp. 147-158 ◽  
Author(s):  
Sampada S. Kharade ◽  
Mark J. McBride
Keyword(s):  
Cell Surface ◽  
Secretion System ◽  
Gliding Motility ◽  
Content Type ◽  
Flavobacterium Johnsoniae ◽  
Protein Secretion System ◽  
Surface Motility ◽  
Type Ix Secretion System ◽  
Carboxy Terminal ◽  
Novel Protein

Flavobacterium johnsoniaeexhibits gliding motility and digests many polysaccharides, including chitin. A novel protein secretion system, the type IX secretion system (T9SS), is required for gliding and chitin utilization. The T9SS secretes the cell surface motility adhesins SprB and RemA and the chitinase ChiA. Proteins involved in secretion by the T9SS include GldK, GldL, GldM, GldN, SprA, SprE, and SprT.Porphyromonas gingivalishas orthologs for each of these that are required for secretion of gingipain protease virulence factors by its T9SS.P. gingivalisporUandporVhave also been linked to T9SS-mediated secretion, andF. johnsoniaehas orthologs of these. Mutations inF. johnsoniaeporUandporVwere constructed to determine if they function in secretion. Cells of aporVdeletion mutant were deficient in chitin utilization and failed to secrete ChiA. They were also deficient in secretion of the motility adhesin RemA but retained the ability to secrete SprB. SprB is involved in gliding motility and is needed for formation of spreading colonies on agar, and theporVmutant exhibited gliding motility and formed spreading colonies. However, theporVmutant was partially deficient in attachment to glass, apparently because of the absence of RemA and other adhesins on the cell surface. TheporVmutant also appeared to be deficient in secretion of numerous other proteins that have carboxy-terminal domains associated with targeting to the T9SS. PorU was not required for secretion of ChiA, RemA, or SprB, indicating that it does not play an essential role in theF. johnsoniaeT9SS.

scholarly journals Involvement of the Type IX Secretion System in Capnocytophaga ochracea Gliding Motility and Biofilm Formation

2016 ◽  
Vol 82 (6) ◽  
pp. 1756-1766 ◽  
Author(s):  
Daichi Kita ◽  
Satoshi Shibata ◽  
Yuichiro Kikuchi ◽  
Eitoyo Kokubu ◽  
Koji Nakayama ◽  
...  
Keyword(s):  
Cell Surface ◽  
Biofilm Formation ◽  
Laser Scanning ◽  
Secretion System ◽  
Gliding Motility ◽  
Confocal Laser ◽  
Bacterial Cells ◽  
Wild Type ◽  
Content Type ◽  
Type Ix Secretion System

ABSTRACTCapnocytophaga ochraceais a Gram-negative, rod-shaped bacterium that demonstrates gliding motility when cultured on solid agar surfaces.C. ochraceapossesses the ability to form biofilms; however, factors involved in biofilm formation by this bacterium are unclear. A type IX secretion system (T9SS) inFlavobacterium johnsoniaewas shown to be involved in the transport of proteins (e.g., several adhesins) to the cell surface. Genes orthologous to those encoding T9SS proteins inF. johnsoniaehave been identified in the genome ofC. ochracea; therefore, the T9SS may be involved in biofilm formation byC. ochracea. Here we constructed three ortholog-deficientC. ochraceamutants lackingsprB(which encodes a gliding motility adhesin) orgldKorsprT(which encode T9SS proteins inF. johnsoniae). Gliding motility was lost in each mutant, suggesting that, inC. ochracea, the proteins encoded bysprB,gldK, andsprTare necessary for gliding motility, and SprB is transported to the cell surface by the T9SS. For the ΔgldK, ΔsprT, and ΔsprBstrains, the amounts of crystal violet-associated biofilm, relative to wild-type values, were 49%, 34%, and 65%, respectively, at 48 h. Confocal laser scanning and scanning electron microscopy revealed that the biofilms formed by wild-typeC. ochraceawere denser and bacterial cells were closer together than in those formed by the mutant strains. Together, these results indicate that proteins exported by the T9SS are key elements of the gliding motility and biofilm formation ofC. ochracea.

scholarly journals Crystal structures of two camelid nanobodies raised against GldL, a component of the type IX secretion system from Flavobacterium johnsoniae

2021 ◽  
Vol 77 (6) ◽  
Author(s):  
Thi Trang Nhung Trinh ◽  
Anaïs Gaubert ◽  
Pauline Melani ◽  
Christian Cambillau ◽  
Alain Roussel ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Cytoplasmic Domain ◽  
Secretion System ◽  
Gliding Motility ◽  
Molecular Replacement ◽  
Flavobacterium Johnsoniae ◽  
Type Ix Secretion System ◽  
Inner Membrane Protein ◽  
And Function ◽  
Rotary Motor

GldL is an inner-membrane protein that is essential for the function of the type IX secretion system (T9SS) in Flavobacterium johnsoniae. The complex that it forms with GldM is supposed to act as a new rotary motor involved in the gliding motility of the bacterium. In the context of structural studies of GldL to gain information on the assembly and function of the T9SS, two camelid nanobodies were selected, produced and purified. Their interaction with the cytoplasmic domain of GldL was characterized and their crystal structures were solved. These nanobodies will be used as crystallization chaperones to help in the crystallization of the cytoplasmic domain of GldL and could also help to solve the structure of the complex using molecular replacement.

scholarly journals Cytophaga hutchinsonii SprA and SprT Are Essential Components of the Type IX Secretion System Required for Ca2+ Acquisition, Cellulose Degradation, and Cell Motility

2021 ◽  
Vol 12 ◽  
Author(s):  
Lijuan Gao ◽  
Yahong Tan ◽  
Weican Zhang ◽  
Qingsheng Qi ◽  
Xuemei Lu
Keyword(s):  
Cell Surface ◽  
Protein Secretion ◽  
Cellulose Degradation ◽  
Secretion System ◽  
Gliding Motility ◽  
Uptake System ◽  
Cytophaga Hutchinsonii ◽  
Essential Components ◽  
Single Deletion ◽  
Type Ix Secretion System

The type IX secretion system (T9SS) is a novel protein secretion system, which is found in and confined to the phylum Bacteroidetes. T9SS is involved in the secretion of virulence factors, cell surface adhesins, and complex biopolymer degrading enzymes to the cell surface or extracellular medium. Cytophaga hutchinsonii is a widely distributed bacterium, which is able to efficiently digest cellulose and rapidly glide along the solid surfaces. C. hutchinsonii has a full set of orthologs of T9SS components. However, the functions of most homologous proteins have not been verified. In C. hutchinsonii, CHU_0029 and CHU_2709 are similar in sequence to Flavobacterium johnsoniae T9SS components SprA and SprT, respectively. In this study, the single deletion mutants of chu_0029 (sprA) and chu_2709 (sprT) were obtained using a complex medium with the addition of Ca2+ and Mg2+. Single deletion of sprA or sprT resulted in defects in cellulose utilization and gliding motility. Moreover, the ΔsprA and ΔsprT mutants showed growth defects in Ca2+- and Mg2+-deficient media. The results of ICP-MS test showed that both the whole cell and intracellular concentrations of Ca2+ were dramatically reduced in the ΔsprA and ΔsprT mutants, indicating that SprA and SprT are both important for the assimilation of trace amount of Ca2+. While the assimilation of Mg2+ was not obviously influenced in the ΔsprA and ΔsprT mutants. Through proteomics analysis of the cell surface proteins of the wild type and mutants, we found that the ΔsprA and ΔsprT mutants were defective in secretion of the majority of T9SS substrates. Together, these results indicate that SprA and SprT are both essential components of C. hutchinsonii T9SS, which is required for protein secretion, Ca2+ acquisition, cellulose degradation, and gliding motility in C. hutchinsonii. Our study shed more light on the functions of SprA and SprT in T9SS, and further proved the link between the T9SS and Ca2+ uptake system.

Sign in / Sign up

Export Citation Format

Share Document