Velasco-Amo María Pilar, Arias-Giraldo Luis F, Olivares-García Concepción, Denancé Nicolás, Jacques Marie-Agnès, Landa Blanca B
Institute for Sustainable Agriculture (IAS), Spanish National Research Council (CSIC), 14004 Córdoba, Spain.
Groupe d'Étude et de controle des Variétes Et des Semences GEVES, CEDEX, F-49071 Beaucouzé, France.
Plants (Basel). 2022 Jun 13;11(12):1562. doi: 10.3390/plants11121562.
() is a phytopathogenic bacterium with a repertoire of self-replicating genetic elements, including plasmids, pathogenicity islands, and prophages. These elements provide potential avenues for horizontal gene transfer both within and between species and have the ability to confer new virulence traits, including the ability to colonize new host plants. However, they can also serve as a 'footprint' to type plasmid-bearing strains. Genome sequencing of several strains of subsp. sequence type (ST) 1 from Mallorca Island, Spain, revealed the presence of a 38 kb plasmid (pXFAS_5235). In this study, we developed a PCR-based typing approach using primers targeting the gene to determine the presence of pXFAS_5235 plasmid or other plasmids carrying this gene in a world-wide collection of 65 strains from different subspecies and STs or in 226 plant samples naturally infected by the bacterium obtained from the different outbreaks of in Spain. The gene was amplified only in the plant samples obtained from Mallorca Island infected by subsp. ST1 and from all Spanish strains belonging to this ST. Maximum-likelihood phylogenetic tree of C revealed a close relatedness among Spanish and Californian strains carrying similar plasmids. Our results confirm previous studies, which suggested that a single introduction event of subsp. ST1 occurred in the Balearic Islands. Further studies on the presence and role of plasmids in strains belonging to the same or different subspecies and STs can provide important information in studies of epidemiology, ecology, and evolution of this plant pathogen.
（）是一种植物致病细菌，具有一系列自我复制的遗传元件，包括质粒、致病岛和原噬菌体。这些元件为物种内部和物种之间的水平基因转移提供了潜在途径，并具有赋予新毒力特性的能力，包括定殖新宿主植物的能力。然而，它们也可作为鉴定携带质粒菌株的“足迹”。对来自西班牙马略卡岛的几个序列型（ST）1亚种菌株进行全基因组测序，发现了一个38 kb的质粒（pXFAS_5235）。在本研究中，我们开发了一种基于PCR的分型方法，使用靶向该基因的引物，以确定在来自不同亚种和ST的65个菌株的全球收集物中，或在从西班牙不同疫情中获得的226个自然感染该细菌的植物样本中，是否存在pXFAS_5235质粒或携带该基因的其他质粒。该基因仅在来自马略卡岛感染亚种ST1的植物样本以及所有属于该ST的西班牙菌株中扩增。C的最大似然系统发育树显示，携带相似质粒的西班牙和加利福尼亚菌株之间存在密切相关性。我们的结果证实了先前的研究，即亚种ST1在巴利阿里群岛发生了单次引入事件。对属于相同或不同亚种和ST的菌株中质粒的存在和作用进行进一步研究，可以为这种植物病原体的流行病学、生态学和进化研究提供重要信息。
