Genetic elucidation of the functional and regulatory mechanisms underlying the Type IV Secretion System in Xanthomonas citri and how it mediates contact dependent killing

• Grant number: 15/18237-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: February 01, 2016
• End date: May 31, 2019
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: Shaker Chuck Farah
• Grantee: William Cenens
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 17/17303-7 - Structure and function of bacterial secretion systems, AP.TEM

Abstract

During Type IV Secretion System (T4SS) mediated killing of neighboring bacterial cells by Xanthomonas citri (Xac), several effector proteins are secreted and injected into the target cell by a contact dependent mechanism. As a first objective the function of these effector proteins will be investigated. Assessing the activity of different effector deletion mutants against different bacterial species will allow discrimination between the antibacterial and regulatory effects of the individual effector proteins. Additionally, the ectopic and conditional expression of antibacterial effector proteins combined with protein interaction studies will point to their cellular targets. A second objective involves whole-genome transposon insertion strategies to retrieve all loci involved during competition of Xac with other bacterial species. A first straightforward classical transposon screen will reveal the clear-cut mutants and this search will be expanded by a Tn-seq approach, drastically increasing our genetic view on the interbacterial competition of Xac. Additionally, this objective could also reveal alternative mechanisms working either independently or together with the T4SS during interbacterial competition. As a final objective, the regulation, assembly and localization of the T4SS during contact with target cells will be further analyzed by combining time-lapse fluorescence microscopy with different fluorescent labeling approaches.

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

LLONTOP, EDGAR E.; CENENS, WILLIAM; FAVARO, DENIZE C.; SGRO, GERMAN G.; SALINAS, ROBERTO K.; GUZZO, CRISTIANE R.; FARAH, CHUCK S.. he PilB-PilZ-FimX regulatory complex of the Type IV pilus from Xanthomonas citr. PLOS PATHOGENS, v. 17, n. 8, AUG 2021. (15/18237-2, 19/12234-2, 17/17303-7)

OKA, GABRIEL U.; SOUZA, DIORGE P.; CENENS, WILLIAM; MATSUYAMA, BRUNO Y.; CARDOSO, MARCUS V. C.; OLIVEIRA, LUCIANA C.; LIMA, FILIPE DA SILVA; CUCCOVIA, IOLANDA M.; GUZZO, CRISTIANE R.; SALINAS, ROBERTO K.; et al. tructural basis for effector recognition by an antibacterial type IV secretion syste. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, v. 119, n. 1, JAN 4 2022. (18/09277-9, 15/18237-2, 17/17303-7, 16/00458-5)

CENENS, WILLIAM; ANDRADE, MAXUEL O.; LLONTOP, EDGAR; ALVAREZ-MARTINEZ, CRISTINA E.; SGRO, GERMAN G.; FARAH, CHUCK S.. Bactericidal type IV secretion system homeostasis in Xanthomonas citri. PLOS PATHOGENS, v. 16, n. 5, MAY 2020. (19/12234-2, 15/18237-2, 14/04294-1, 17/17303-7, 11/07777-5)

BAYER-SANTOS, ETHEL; CENENS, WILLIAM; MATSUYAMA, BRUNO YASUI; OKA, GABRIEL UMAJI; DI SESSA, GIANCARLO; MININEL, IZABEL DEL VALLE; ALVES, TIAGO LUBIANA; FARAH, CHUCK SHAKER. The opportunistic pathogen Stenotrophomonas maltophilia utilizes a type IV secretion system for interbacterial killing. PLOS PATHOGENS, v. 15, n. 9, SEP 2019. (15/25381-2, 17/17303-7, 18/04553-8, 15/18237-2, 17/02178-2, 16/00458-5, 11/07777-5)