Article
Microbiology
Sophie A. Howard, R. Christopher D. Furniss, Dora Bonini, Himani Amin, Patricia Paracuellos, David Zlotkin, Tiago R. D. Costa, Asaf Levy, Despoina A. I. Mavridou, Alain Filloux
Summary: The T6SS is a bacterial nanoscale weapon that delivers toxins into prey and plays a key role in the arms race between organisms. By using Hcp as bait, researchers identified uncharacterized toxins and investigated the role of Hcp in the T6SS mechanism.
Review
Biochemistry & Molecular Biology
Amit Meir, Kevin Mace, Yogesh Vegunta, Sunanda M. Williams, Gabriel Waksman
Summary: This review provides an update on recent advances in substrate recruitment and delivery by recruitment platforms associated with Type III, IV, and VI secretion systems in gram-negative bacteria.
TRENDS IN MICROBIOLOGY
(2023)
Article
Microbiology
Chaya Mushka Fridman, Biswanath Jana, Rotem Ben-Yaakov, Eran Bosis, Dor Salomon
Summary: Specialized protein delivery systems are used during bacterial competition to deploy cocktails of toxins that target conserved cellular components. Although numerous toxins have been revealed, the activity of many remains unknown. In this study, we investigated such a toxin from the pathogen Vibrio parahaemolyticus. Our findings indicate that the toxin employs a DNase domain to intoxicate competitors. We also show that a domain used as a marker for secreted toxins is required for secretion of the toxin via a type VI secretion system.
MICROBIOLOGY SPECTRUM
(2022)
Review
Cell Biology
Flavia Viana, Shruthi Sachidanandan Peringathara, Arshad Rizvi, Gunnar N. Schroeder
Summary: Proteases are powerful enzymes that irreversibly cleave peptide bonds to control critical cell fate decisions. Bacterial pathogens deliver protease effectors through secretion systems to manipulate host processes, with functional diversity reflecting adaptations to specific hosts. Emerging concepts like effector-triggered immunity provide insights into host defense against protease attacks.
CELLULAR MICROBIOLOGY
(2021)
Article
Microbiology
Dustin E. Bosch, Romina Abbasian, Bishal Parajuli, S. Brook Peterson, Joseph D. Mougous
Summary: Bacteroidales are associated with the severity and progression of inflammatory bowel disease. We have identified the type VI secretion system nuclease effectors (Tde) that are enriched in ulcerative colitis and transferred through mobile genetic elements. Tde-encoding T6SSs mediate interbacterial competition. The orphan and cognate immunity proteins (Tdi) prevent intoxication by multiple Tde through a unique mechanism. This mechanism allows for broad neutralization of Tde by orphan Tdi and may contribute to Bacteroidales diversity in the context of ulcerative colitis.
Article
Biochemistry & Molecular Biology
Yasmin Dar, Biswanath Jana, Eran Bosis, Dor Salomon
Summary: A new bacterial secretion mechanism, termed a binary effector module, has been identified where an effector and co-effector are secreted together. This mechanism is widely distributed in marine bacteria and involves direct interaction between the effector and co-effector.
Article
Microbiology
Jingjing Luo, Xiao Chu, Jing Jie, Yu Sun, Qingtian Guan, Dan Li, Zhao-Qing Luo, Lei Song
Summary: This study reveals that Acinetobacter baumannii uses its type VI secretion system (T6SS) to kill fungi, with the effector TafE responsible for this antifungal activity. A. baumannii protects itself from the toxicity of TafE by secreting the immunity protein TaeI. This discovery sheds light on the survival mechanism of A. baumannii in complex environments and has implications for the development of novel preventive and treatment measures.
Article
Microbiology
Luca Robinson, Janie Liaw, Zahra Omole, Dong Xia, Arnoud H. M. van Vliet, Nicolae Corcionivoschi, Abderrahman Hachani, Ozan Gundogdu
Summary: The Type VI Secretion System (T6SS) plays crucial roles in bacterial antagonism, subversion of host cells, and niche colonisation. A unique and conserved T6SS cluster associated with Campylobacter jejuni Integrated Element 3 (CJIE3) was identified as Campylobacter jejuni Pathogenicity Island-1 (CJPI-1), which contains canonical VgrG homologues and a Type II toxin-antitoxin module.
FRONTIERS IN MICROBIOLOGY
(2021)
Review
Biochemistry & Molecular Biology
Julia Sanchez-Garrido, David Ruano-Gallego, Jyoti S. Choudhary, Gad Frankel
Summary: Recent studies have shown that T3SS effectors interact with each other in the host, revealing their interdependency and context-dependent essentiality, which is of great significance for understanding the pathogenesis of the pathogens.
TRENDS IN MICROBIOLOGY
(2022)
Article
Microbiology
Nicole A. Loeven, Andrew Perault, Peggy A. Cotter, Craig A. Hodges, Joseph D. Schwartzman, Thomas H. Hampton, James B. Bliska
Summary: Burkholderia cenocepacia is a highly virulent member of the Burkholderia cepacia complex (Bcc), strongly associated with cepacia syndrome. The T6SS effector TecA exacerbates lung inflammation, weight loss, and lethality in mouse infection models, establishing TecA as a key virulence factor. Further studies are needed to understand TecA's role and develop strategies to prevent or treat B. cenocepacia infections.
Article
Veterinary Sciences
Cang Chen, Yimin Dai, Yingying Yang, Zihe Zhu, Qinghua Zhang, Xuejiao An, Fenju Lai
Summary: This study shows that LI0666 is an authentic bacterial EPIYA effector. This finding provides insights into the molecular mechanisms of LI0666 in disease development.
VETERINARY RESEARCH
(2022)
Article
Biochemistry & Molecular Biology
Neil Lorente Cobo, Stephanie Sibinelli-Sousa, Jacob Biboy, Waldemar Vollmer, Ethel Bayer-Santos, Gerd Prehna
Summary: This study reveals the structure and function of the T6SS effector Tlde1a from Salmonella Typhimurium. Tlde1a possesses a unique LD-transpeptidase fold, which is structurally altered to create its toxic effect and plays an important role in bacterial competition.
JOURNAL OF BIOLOGICAL CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Jake Colautti, Nathan P. Bullen, John C. Whitney
Summary: This study replicated previous findings and found that cells lacking PA0808 are not susceptible to AmpDh3, and there is no physical interaction between PA0808 and AmpDh3 in vitro or in vivo. Additionally, there is no evidence that AmpDh3 is exported from cells. These results cast doubt on the assertion that AmpDh3-PA0808 constitutes an H2-T6SS effector-immunity pair.
MOLECULAR MICROBIOLOGY
(2023)
Article
Multidisciplinary Sciences
Gabriel U. Oka, Diorge P. Souza, William Cenens, Bruno Y. Matsuyama, Marcus V. C. Cardoso, Luciana C. Oliveira, Filipe da Silva Lima, Iolanda M. Cuccovia, Cristiane R. Guzzo, Roberto K. Salinas, Chuck S. Farah
Summary: The study identified an interaction between XVIPCD and VirD4, dividing XVIPCD into two regions with distinct functions. The N-terminal region interacts with VirD4, while both the N- and C-terminal regions are required for efficient X-Tfe translocation into target cells. The conformational stability of the N-terminal region is reduced at lower pH, potentially facilitating X-Tfe unfolding and translocation.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Editorial Material
Biochemistry & Molecular Biology
Sophie Robitaille, Evan Trus, Benjamin D. Ross
Summary: Bacteria have developed various systems for interbacterial competition, such as physical barriers, genetically encoded antidotes, and stress responses. Further research will reveal the interbacterial selective pressures impacting bacterial survival in nature.
TRENDS IN MICROBIOLOGY
(2021)
