RESUMEN
Pseudomonas syringae pv. actinidiae is a bacterial pathogen of kiwifruit. Based on the results of the pathogenicity assay, we sequenced the strain Pseudomonas syringae (Psa3) P155 which possesses a series of virulence and resistance genes, CRISPR candidate elements, prophage related sequences, methylation modifications, genomic islands as well as one plasmid. Most importantly, the copper resistance genes copA, copB, copC, copD, and copZ as well as aminoglycoside resistance gene ksgA were identified in strain P155, which would pose a threat to kiwifruit production. The complete sequence we reported here will provide valuable information for a better understanding of the genetic structure and pathogenic characteristics of the genome of P155.
Pseudomonas syringae pv. actinidiae agente causal do cancro bacteriano do kiwi. Com base nos resultados do teste de patogenicidade, foi sequenciado um isolado de Pseudomonas syringae (Psa3) P155, que abriga a uma série de genes de virulência e resistência, elementos candidatos CRISPR, sequências relacionadas a profagos, modificações na metilação, ilhas genômicas, e também um plasmídeo. O mais importante foram os genes de resistência ao cobre, copA, copB, copC, copD e copZ, bem como, o gene de resistência aminoglicosídea ksgA identificados na estirpe P155, os quais representariam uma ameaça à produção de kiwi. A sequência completa relatada fornecerá informações valiosas para uma melhor compreensão da estrutura genética e as características patogênicas do genoma de P155.
Asunto(s)
Virulencia , Actinidia , Pseudomonas syringae , Secuenciación Completa del GenomaRESUMEN
Class III peroxidase (CIII prx) is a plant-specific multigene family that regulates the physiological and stress responses. This research aimed to exhaustively annotate and analyse the CIII prx family in sweet orange and to explore the regulated expression profiles by Xanthomonas citri subsp. citri (Xcc) and plant hormones. We further assessed the relationship between CIII prxs and citrus bacterial canker. The phylogeny, gene structure, conserved motifs, gene duplications and microsynteny of the CIII prx family were analysed. Expression profiles of specific CsPrxs induced by Xanthomonas citri subsp. citri and plant hormones were detected by quantitative reverse transcription-polymerase chain reaction. Subcellular localization was analysed through transient expression assessments. A total of 72 CIII prx members were identified from the genomes of sweet orange. In all chromosomes of sweet orange, the CsPrxs could be detected except in chromosome 8. In addition, three segmental duplications, four tandem duplications and 11 whole-genome duplications occurred among the CsPrxs, contributing to the family size expansion. From the Ka/Ks ratios, 15 of 18 duplicated CsPrxs pairs have experienced purifying selection process. A total of 15 conserved motifs were detected in CsPrxs, four of which were detected in all complete CsPrxs. A total of 12 expressed genes were identified from the EST database. The expression trends of 12 CsPrxs were differently expressed at different stages of infection by Xcc, five of which were potential candidate genes involved in Xcc resistance. These genes could be induced by salicylic acid and methyl jasmonate, and were extracellular proteins. These results further support our understanding of CIII prxs in citrus, particularly in citrus bacterial canker studies