Analysis of CRISPR-Cas loci distribution in Xanthomonas citri and its possible control by the quorum sensing system

Autor(es)

Martins, Paula Maria Moreira ; Granato, Lais Moreira ; Morgan, Tulio ; Nalin, Julia Lopes ; Takita, Marco Aurelio ; Alfenas-Zerbini, Poliane ; de Souza, Alessandra Alves

• Tipo de documento: Artigo Científico
• Fonte: FEMS Microbiology Letters; v. 371, p. 10-pg., 2024-02-14.

Resumo

Xanthomonas is an important genus of plant-associated bacteria that causes significant yield losses of economically important crops worldwide. Different approaches have assessed genetic diversity and evolutionary interrelationships among the Xanthomonas species. However, information from clustered regularly interspaced short palindromic repeats (CRISPRs) has yet to be explored. In this work, we analyzed the architecture of CRISPR-Cas loci and presented a sequence similarity-based clustering of conserved Cas proteins in different species of Xanthomonas. Although absent in many investigated genomes, Xanthomonas harbors subtype I-C and I-F CRISPR-Cas systems. The most represented species, Xanthomonas citri, presents a great diversity of genome sequences with an uneven distribution of the CRISPR-Cas systems among the subspecies/pathovars. Only X. citri subsp. citri and X. citri pv. punicae have these systems, exclusively of subtype I-C system. Moreover, the most likely targets of the X. citri CRISPR spacers are viruses (phages). At the same time, few are plasmids, indicating that CRISPR/Cas system is possibly a mechanism to control the invasion of foreign DNA. We also showed in X. citri susbp. citri that the cas genes are regulated by the diffusible signal factor, the quorum sensing (QS) signal molecule, according to cell density increases, and under environmental stress like starvation. These results suggest that the regulation of CRISPR-Cas by QS occurs to activate the gene expression only during phage infection or due to environmental stresses, avoiding a possible reduction in fitness. Although more studies are needed, CRISPR-Cas systems may have been selected in the Xanthomonas genus throughout evolution, according to the cost-benefit of protecting against biological threats and fitness maintenance in challenging conditions. The presence and distribution of clustered regularly interspaced short palindromic repeat-associated sequence loci in Xanthomonas, with potencial regulatation by the quorum sensing mechanism. (AU)

• Processo FAPESP: 20/07045-3 - Estratégias biotecnológicas e genômicas para qualidade, produtividade e manejo sustentável de citros, café e cana-de-açúcar no estado de São Paulo
• Beneficiário: Mariângela Cristofani-Yaly
• Modalidade de apoio: Auxílio à Pesquisa - Núcleos de Pesquisa Orientada a Problemas em São Paulo
• Processo FAPESP: 16/01273-9 - Sistemas toxina-antitoxina em Xanthomonas citri subsp citri: função e estratégia para indução de morte celular programada
• Beneficiário: Paula Maria Moreira Martins
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/10957-0 - Interação Xylella fastidiosa-inseto vetor-planta hospedeira e abordagens para o controle da clorose variegada dos citros e cancro cítrico
• Beneficiário: Alessandra Alves de Souza
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 14/50880-0 - INCT 2014: de genômica comparativa e funcional e melhoramento assistido de citros
• Beneficiário: Marcos Antonio Machado
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 19/01901-8 - Silenciamento gênico do floema cítrico: modulação da hipersensibilidade à infecção por Candidatus liberibacter spp
• Beneficiário: Laís Moreira Granato
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado