Characterisation of candidate effectors of the Xanthomonas citri pv. citri type 6 secretion system using the Dictyostelium discoideum model

• Grant number: 20/11140-1
• Support type: Scholarships abroad - Research Internship - Doctorate (Direct)
• Effective date (Start): January 01, 2022
• Effective date (End): March 31, 2022
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal researcher: Cristina Elisa Alvarez Martinez
• Grantee: Lucas de Moraes Ceseti
• Supervisor abroad: Thierry Soldati
• Home Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Research place: Université de Genève, Switzerland
• Associated to the scholarship: 17/02318-9 - Functional studies of the Xanthomonas citri pv. citri type 6 secretion system: secreted proteins, recruitment and regulation, BP.DD

Abstract

Type 6 Secretion Systems (T6SS) are bacterial nanomachines that deliver effector proteins or toxins directly into prokaryotic and/or eukaryotic target cells. These devices are involved in the interspecific competition and virulence playing fundamental roles in bacterial fitness in their ecological niches. The T6SS of Xanthomonas citri pv citri is required for resistance against the bacterivorous amoeba Dictyostelium discoideum, revealing an aspect of X. citri biology. The protein effectors enrolled in this interaction remain elusive. Hence, we aim to develop a new tool to directly monitor and visualize the translocation of candidate effectors of the X. citri T6SS in vivo. Concurrently, the effect of ectopic expression of these candidates on D. discoideum physiology will be analyzed to unveil their mode of action and targets in the eukaryotic cell. Results obtained will significantly contribute to the understanding of the molecular mechanisms involved in bacterial resistance against predation, possibly leading to the identification of new T6SS protein effectors in bacteria and opening new possibilities for the control of this important phytopathogen in the environment. (AU)