Biology Department, Faculty of Sciences, University of Porto, Porto, Portugal.
LAQV-REQUIMTE, Faculty of Sciences, University of Porto, Porto, Portugal.
PeerJ. 2022 Jul 21;10:e13695. doi: 10.7717/peerj.13695. eCollection 2022.
Fire blight is a destructive disease of pome trees, caused by , leading to high losses of chain-of-values fruits. Major outbreaks were registered between 2010 and 2017 in Portugal, and the first molecular epidemiological characterization of those isolates disclosed a clonal population with different levels of virulence and susceptibility to antimicrobial peptides.
This work aimed to further disclose the genetic characterization and unveil the phenotypic diversity of this population, resorting to MLSA, growth kinetics, biochemical characterization, and antibiotic susceptibility.
While MLSA further confirmed the genetic clonality of those isolates, several phenotypic differences were recorded regarding their growth, carbon sources preferences, and chemical susceptibility to several antibiotics, disclosing a heterogeneous population. Principal component analysis regarding the phenotypic traits allows to separate the strains Ea 630 and Ea 680 from the remaining.
Regardless the genetic clonality of these strains isolated from fire blight outbreaks, the phenotypic characterization evidenced a population diversity beyond the genotype clonality inferred by MLSA and CRISPR, suggesting that distinct sources or environmental adaptations of this pathogen may have occurred.
Attending the characteristic clonality of species, the data gathered here emphasizes the importance of phenotypic assessment of isolates to better understand their epidemiological behavior, namely by improving source tracking, make risk assessment analysis, and determine strain-specific environmental adaptations, that might ultimately lead to prevent new outbreaks.
火疫病是一种毁灭性的核果树木病害，由 引起，导致价值链水果的大量损失。2010 年至 2017 年期间，葡萄牙曾发生过几次大规模疫情，对这些分离株的首次分子流行病学特征分析揭示了一个具有不同毒力和对抗菌肽敏感性水平的克隆种群。
本研究旨在进一步揭示该种群的遗传特征，并揭示其表型多样性，采用 MLSA、生长动力学、生化特征和抗生素敏感性分析。
虽然 MLSA 进一步证实了这些分离株的遗传克隆性，但在其生长、碳源偏好和对几种抗生素的化学敏感性方面记录了一些表型差异，揭示了一个异质种群。关于表型特征的主成分分析允许将 Ea 630 和 Ea 680 菌株与其余菌株分开。
尽管这些从火疫病疫情中分离出来的菌株具有遗传克隆性，但表型特征表明，该病原体的种群多样性超出了 MLSA 和 CRISPR 推断的基因型克隆性，表明可能发生了不同的来源或环境适应。
鉴于 种的特征克隆性，这里收集的数据强调了对 分离株进行表型评估的重要性，以便更好地了解其流行病学行为，特别是通过改进来源追踪、进行风险评估分析和确定菌株特异性环境适应，这最终可能有助于预防新的疫情爆发。
