Moreira Leandro M, Soares Márcia R, Facincani Agda P, Ferreira Cristiano B, Ferreira Rafael M, Ferro Maria I T, Gozzo Fábio C, Felestrino Érica B, Assis Renata A B, Garcia Camila Carrião M, Setubal João C, Ferro Jesus A, de Oliveira Julio C F
Departamento de Ciências Biológicas (DECBI), Instituto de Ciências Exatas e Biológicas (ICEB), Universidade Federal de Ouro Preto (UFOP), Ouro Preto, MG, Brazil.
Núcleo de Pesquisas em Ciências Biológicas (NUPEB), Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil.
BMC Microbiol. 2017 Jul 11;17(1):155. doi: 10.1186/s12866-017-1063-x.
Xanthomonas citri subsp. citri (Xac) is the causal agent of citrus canker. A proteomic analysis under in planta infectious and non-infectious conditions was conducted in order to increase our knowledge about the adaptive process of Xac during infection.
For that, a 2D-based proteomic analysis of Xac at 1, 3 and 5 days after inoculation, in comparison to Xac growth in NB media was carried out and followed by MALDI-TOF-TOF identification of 124 unique differentially abundant proteins. Among them, 79 correspond to up-regulated proteins in at least one of the three stages of infection. Our results indicate an important role of proteins related to biofilm synthesis, lipopolysaccharides biosynthesis, and iron uptake and metabolism as possible modulators of plant innate immunity, and revealed an intricate network of proteins involved in reactive oxygen species adaptation during Plants` Oxidative Burst response. We also identified proteins previously unknown to be involved in Xac-Citrus interaction, including the hypothetical protein XAC3981. A mutant strain for this gene has proved to be non-pathogenic in respect to classical symptoms of citrus canker induced in compatible plants.
This is the first time that a protein repertoire is shown to be active and working in an integrated manner during the infection process in a compatible host, pointing to an elaborate mechanism for adaptation of Xac once inside the plant.
柑橘溃疡病菌（Xanthomonas citri subsp. citri，Xac）是柑橘溃疡病的病原菌。为了增进我们对Xac在感染过程中适应性过程的了解，开展了在植物体内感染和非感染条件下的蛋白质组学分析。
为此，对接种后1天、3天和5天的Xac进行了基于二维的蛋白质组学分析，并与Xac在NB培养基中的生长情况进行了比较，随后通过基质辅助激光解吸电离飞行时间串联质谱（MALDI-TOF-TOF）鉴定了124种独特的差异丰富蛋白。其中，79种对应于感染三个阶段中至少一个阶段上调的蛋白。我们的结果表明，与生物膜合成、脂多糖生物合成以及铁摄取和代谢相关的蛋白作为植物先天免疫的可能调节因子具有重要作用，并揭示了植物氧化爆发反应期间参与活性氧适应的复杂蛋白网络。我们还鉴定了以前未知参与Xac与柑橘相互作用的蛋白，包括假定蛋白XAC3981。已证明该基因的突变菌株对在亲和植物中诱导的柑橘溃疡病经典症状无致病性。
这是首次表明在亲和宿主的感染过程中，一组蛋白质以整合的方式发挥作用，这表明Xac一旦进入植物体内就有一个复杂的适应机制。
