Characterization of target genes MqsR toxin in Xylella fastidiosa: regulatory function and formation of persistent cells

• Grant number: 16/15741-4
• Support Opportunities: Scholarships in Brazil - Master
• Start date: October 01, 2016
• End date: February 28, 2018
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Alessandra Alves de Souza
• Grantee: Isis Gabriela Barbosa Carvalho
• Host Institution: Instituto Agronômico (IAC). Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). Campinas , SP, Brazil

Abstract

The citrus industry is one of the most important agribusinesses in Brazil, especially in world production of orange juice. However, due to phytosanitary problems, there was an increase in the cost of production and consequent decrease in planted area providing lower yields than expected. Some diseases fall into this context and one of them is the Citrus Variegated Chlorosis (CVC), caused by the bacterium Xylella fastidiosa, which had its genome sequenced so that their biology were better known. Among many studies which followed, it was found that this bacterium has operons encoding the toxin-antitoxin (TA) system. These functions are passing from the maintenance of plasmids to regulatory responses to modulation key genes for bacterial adaptation to adverse conditions in the environment. For example, overexpression of MqsR toxin (a ribonuclease which degrades mRNAs with motifs GCU) in X. fastidiosa induces an increase in biofilm formation, cell movement repression and lack of pathogenicity in plants. Further, increase in the expression levels of MqsR toxin was observed when exposed to X. fastidiosa was copper, an antimicrobial compound, producing changes in cells, such as inducing the formation of persistent cells. These are physiological variants of the cell and are able to survive even when exposed to lethal levels of toxic compounds. The detailed mechanism by which this process occurs is not yet fully known, it is therefore of great interest to identify target sequences of genes regulated by MqsR toxin, so that they can better understand the role of this toxin in gene regulation and induction persistent cells in X. fastidiosa.

Scientific publications

(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)

DE SOUZA-NETO, REINALDO RODRIGUES; BARBOSA CARVALHO, ISIS GABRIELA; MOREIRA MARTINS, PAULA MARIA; PICCHI, SIMONE CRISTINA; TOMAZ, JUAREZ PIRES; CASERTA, RAQUEL; TAKITA, MARCO AURELIO; DE SOUZA, ALESSANDRA ALVES. qsR toxin as a biotechnological tool for plant pathogen bacterial contro. SCIENTIFIC REPORTS, v. 12, n. 1, FEB 18 2022. (17/13885-1, 17/16142-0, 13/10957-0, 16/15741-4, 14/50880-0, 16/01273-9)

CARVALHO, ISIS GABRIELA BARBOSA; MERFA, MARCUS VINICIUS; TEIXEIRA-SILVA, NATALIA SOUSA; MARTINS, PAULA MARIA MOREIRA; TAKITA, MARCO AURELIO; DE SOUZA, ALESSANDRA ALVES. Overexpression of mqsR in Xylella fastidiosa Leads to a Priming Effect of Cells to Copper Stress Tolerance. FRONTIERS IN MICROBIOLOGY, v. 12, SEP 20 2021. (19/01447-5, 14/50880-0, 16/15741-4, 13/10957-0)