Abstract:
Fungal phytopathogens cause significant reductions in agricultural yields annually, and overusing chemical fungicides for their control leads to environmental pollution and the emergence of resistant pathogens. Exploring natural isolates with strong antagonistic effects against pathogens can improve our understanding of their ecology and develop new treatments for the future. We isolated and characterized a novel bacterial strain associated with the species Burkholderia cenocepacia, termed APO9, which strongly inhibits Zymoseptoria tritici, a commercially important pathogenic fungus causing Septoria tritici blotch in wheat. Additionally, this strain exhibits inhibitory activity against four other phytopathogens. We found that physical contact plays a crucial role for APO9\'s antagonistic capacity. Genome sequencing of APO9 and biosynthetic gene cluster (BGC) analysis identified nine classes of BGCs and three types of secretion systems (types II, III, and IV), which may be involved in the inhibition of Z. tritici and other pathogens. To identify genes driving APO9\'s inhibitory activity, we screened a library containing 1,602 transposon mutants and identified five genes whose inactivation reduced inhibition efficiency. One such gene encodes for a diaminopimelate decarboxylase located in a terpenoid biosynthesis gene cluster. Phylogenetic analysis revealed that while some of these genes are also found across the Burkholderia genus, as well as in other Betaproteobacteria, the combination of these genes is unique to the Burkholderia cepacia complex. These findings suggest that the inhibitory capacity of APO9 is complex and not limited to a single mechanism, and may play a role in the interaction between various Burkholderia species and various phytopathogens within diverse plant ecosystems.
OBJECTIVE: The detrimental effects of fungal pathogens on crop yields are substantial. The overuse of chemical fungicides contributes not only to environmental pollution but also to the emergence of resistant pathogens. Investigating natural isolates with strong antagonistic effects against pathogens can improve our understanding of their ecology and develop new treatments for the future. We discovered and examined a unique bacterial strain that demonstrates significant inhibitory activity against several phytopathogens. Our research demonstrates that this strain has a wide spectrum of inhibitory actions against plant pathogens, functioning through a complex mechanism. This plays a vital role in the interactions between plant microbiota and phytopathogens.
摘要:
真菌植物病原体每年导致农业产量显着下降,过度使用化学杀菌剂进行控制会导致环境污染和抗性病原体的出现。探索对病原体具有强烈拮抗作用的天然分离株可以提高我们对其生态学的理解,并为未来开发新的治疗方法。我们分离并鉴定了与伯克霍尔德氏菌有关的新型细菌菌株,称为APO9,它强烈抑制黑麦,一种在商业上重要的致病真菌,可引起小麦中的SeptoriaTritici斑点。此外,该菌株对其他四种植物病原体具有抑制活性。我们发现身体接触对APO9的拮抗能力起着至关重要的作用。APO9的基因组测序和生物合成基因簇(BGC)分析确定了九类BGC和三种类型的分泌系统(II型,III,andIV),这可能与Z.tritici和其他病原体的抑制有关。为了鉴定驱动APO9抑制活性的基因,我们筛选了一个包含1,602个转座子突变体的文库,并鉴定了五个失活降低抑制效率的基因。一个这样的基因编码位于萜类生物合成基因簇中的二氨基庚二酸脱羧酶。系统发育分析显示,虽然这些基因中的一些也在伯克霍尔德氏菌属中发现,以及其他Betaproteobacteria,这些基因的组合是洋葱伯克霍尔德菌所特有的。这些发现表明,APO9的抑制能力是复杂的,不限于单一的机制,并可能在各种植物生态系统中的各种伯克霍尔德菌物种与各种植物病原体之间的相互作用中发挥作用。
目的:真菌病原体对作物产量的有害影响是巨大的。化学杀真菌剂的过度使用不仅导致环境污染,而且导致抗性病原体的出现。研究对病原体具有强烈拮抗作用的天然分离株可以提高我们对其生态学的理解,并为未来开发新的治疗方法。我们发现并检查了一种独特的细菌菌株,该菌株对几种植物病原体具有显着的抑制活性。我们的研究表明,该菌株对植物病原体具有广泛的抑制作用,通过复杂的机制运作。这在植物微生物群和植物病原体之间的相互作用中起着至关重要的作用。