西瓜噬酸菌血红素氧化酶基因hemO功能研究

Functional analysis of heme oxygenase gene hemO in Acidovorax citrulli

在生物体中,血红素氧化酶(Heme oxygenase, HemO)在血红素代谢、铁循环和氧化应激等过程中发挥重要作用。在一些病原菌中,血红素氧化酶可参与调控其致病能力。在西瓜噬酸菌(Acidovorax citrulli)中,存在一个编码血红素氧化酶的基因hemO,然而其功能尚未可知。以西瓜噬酸菌Aac5菌株为研究对象,通过基因敲除构建hemO缺失突变体菌株,分析致病力及生物学表型,并检测致病相关基因表达量,初步探究HemO在西瓜噬酸菌中的功能。结果表明,屁mO基因缺失会促进菌株生物膜的形成,并导致菌株运动性、生长能力、致病力降低,显著影响致病相关基因的表达,但不影响病原菌诱导烟草过敏性反应的能力。这表明hemO基因参与西瓜噬酸菌的致病力调控过程。

Heme oxygenase (HemO) plays an important role in the process of heme metabolism, iron cycle and oxidative stress in living organisms. Heme oxygenase can be involved in the regulation of pathogenicity in some pathogenic bacteria. The hemO gene was identified in Acidovorax citrulli genome. However, the biological function of the gene remains unclear. In this study, the hemO mutant strain was constructed by gene knockout, the pathogenicity and biological phenotype were analyzed, and the expression levels of related pathogenetic genes was detected to explore the function of HemO based on the wild type strain Aac5. The results showed that the deletion of hemO gene promoted biofilm formation, caused the decline in motility, growth ability and pathogenicity, and significantly influenced the expression of related pathogenic genes, but did not affect the ability to induce hypersensitive reaction in non-host Nicotiana tabacum. These results indicated hemO is involved in the pathogenic regulation process of A. citrulli.