Structural insights into Pseudomonas aeruginosa Type six secretion system exported effector 8

González-Magaña, Amaia; Sainz-Polo, M.A.; Pretre, Gabriela; Çapuni, Retina; Lucas, María; Altuna, Jon; Montánchez, Itxaso; Fucini, Paola; Albesa‐Jové, David

doi:10.1016/j.jsb.2020.107651

“…8 ). While this manuscript was in preparation a structure for Tse8 was published (RDB: 6TE4) 40 that agrees with the overall conclusions from our homology modelling data.…”

Section: Tse8 Elicits Toxicity By Interacting With the Bacterial Amidotransferase Complexsupporting

confidence: 81%

Identification of Tse8 as a Type VI secretion system toxin from Pseudomonas aeruginosa that targets the bacterial transamidosome to inhibit protein synthesis in prey cells

Nolan

¹

,

Cain

²

,

Clamens

³

et al. 2021

Self Cite

View full text Add to dashboard Cite

The Type VI secretion system (T6SS) is a bacterial nanomachine which delivers toxic effectors to kill competitors or subvert some of their key functions. Here we use tra nsposon d irected i nsertion-site s equencing (TraDIS) to identify T6SS toxins associated with the H1-T6SS, one of the three T6SS machines found in Pseudomonas aeruginosa . This approach identified several putative toxin-immunity pairs, including Tse8-Tsi8. Full characterization of this protein pair demonstrated that Tse8 is delivered by the VgrG1a spike complex into prey cells where it targets the transamidosome, a multiprotein complex involved in protein synthesis in bacteria that lack either one, or both, of the asparagine and glutamine tRNA synthases. Biochemical characterization of the interactions between Tse8 and the transamidosome components GatA, GatB and GatC suggests that the presence of Tse8 alters the fine-tuned stoichiometry of the transamidosome complex, and in vivo assays demonstrate that Tse8 limits the ability of prey cells to synthesize proteins. These data expand the range of cellular components targeted by the T6SS by identifying a T6SS toxin affecting protein synthesis proteins and validate the use of a TraDIS-based global genomics approach to expand the repertoire of T6SS toxins in T6SS-encoding bacteria.

show abstract

Effectiveness ofPseudomonas aeruginosatype VI secretion system relies on toxin potency and type IV pili-dependent interaction

Rudzite

¹

,

Endres

²

,

Filloux

³

2022

Preprint

View full text Add to dashboard Cite

The type VI secretion system (T6SS) is an antibacterial weapon that is used by numerous Gram-negative bacteria to gain competitive advantage by injecting toxins into adjacent prey cells. Predicting the outcome of a T6SS-dependent competition is not only reliant on presence-absence of the system but instead involves a multiplicity of factors. Pseudomonas aeruginosa possesses 3 distinct T6SSs and a set of more than 20 toxic effectors with diverse functions including disruption of cell wall integrity, degradation of nucleic acids or metabolic impairment. We generated a comprehensive collection of mutants with various degrees of T6SS activity and/or sensitivity to each individual T6SS toxin. By imaging whole mixed bacterial macrocolonies, we then investigated how these P. aeruginosa strains gain a competitive edge in multiple attacker/prey combinations. We observed that the potency of single T6SS toxin varies significantly from one another as measured by monitoring the community structure, with some toxins acting better in synergy or requiring a higher payload. Remarkably the degree of intermixing between preys and attackers is also key to the competition outcome and is driven by the frequency of contact as well as the ability of the prey to move away from the attacker using type IV pili-dependent twitching motility. Finally, we implemented a computational model to better understand how changes in T6SS firing behaviours or cell-cell contacts lead to population level competitive advantages, thus providing conceptual insight applicable to all types of contact-based competition.

show abstract

Effectiveness of Pseudomonas aeruginosa type VI secretion system relies on toxin potency and type IV pili-dependent interaction

Rudzite

¹

,

Subramoni

²

,

Endres

³

et al. 2023

View full text Add to dashboard Cite

The type VI secretion system (T6SS) is an antibacterial weapon that is used by numerous Gram-negative bacteria to gain competitive advantage by injecting toxins into adjacent prey cells. Predicting the outcome of a T6SS-dependent competition is not only reliant on presence-absence of the system but instead involves a multiplicity of factors. Pseudomonas aeruginosa possesses 3 distinct T6SSs and a set of more than 20 toxic effectors with diverse functions including disruption of cell wall integrity, degradation of nucleic acids or metabolic impairment. We generated a comprehensive collection of mutants with various degrees of T6SS activity and/or sensitivity to each individual T6SS toxin. By imaging whole mixed bacterial macrocolonies, we then investigated how these P. aeruginosa strains gain a competitive edge in multiple attacker/prey combinations. We observed that the potency of single T6SS toxin varies significantly from one another as measured by monitoring the community structure, with some toxins acting better in synergy or requiring a higher payload. Remarkably the degree of intermixing between preys and attackers is also key to the competition outcome and is driven by the frequency of contact as well as the ability of the prey to move away from the attacker using type IV pili-dependent twitching motility. Finally, we implemented a computational model to better understand how changes in T6SS firing behaviours or cell-cell contacts lead to population level competitive advantages, thus providing conceptual insight applicable to all types of contact-based competition.

show abstract

Structural insights into Pseudomonas aeruginosa Type six secretion system exported effector 8

Cited by 3 publications

References 57 publications

Identification of Tse8 as a Type VI secretion system toxin from Pseudomonas aeruginosa that targets the bacterial transamidosome to inhibit protein synthesis in prey cells

Identification of Tse8 as a Type VI secretion system toxin from Pseudomonas aeruginosa that targets the bacterial transamidosome to inhibit protein synthesis in prey cells

Effectiveness ofPseudomonas aeruginosatype VI secretion system relies on toxin potency and type IV pili-dependent interaction

Effectiveness of Pseudomonas aeruginosa type VI secretion system relies on toxin potency and type IV pili-dependent interaction

Contact Info

Product

Resources

About