Mendoza Hector, Culver Caroline D, Lamb Emma A, Schroeder Luke A, Khanal Sunita, Müller Christian, Schirawski Jan, Perlin Michael H
Department of Biology, Program on Disease Evolution, University of Louisville, Louisville, KY 40292, USA.
Division of Cardiovascular Medicine, School of Medicine, University of Maryland, Baltimore, MD 21201, USA.
J Fungi (Basel). 2022 Jan 31;8(2):148. doi: 10.3390/jof8020148.
The mitochondrial electron transport chain consists of the classical protein complexes (I-IV) that facilitate the flow of electrons and coupled oxidative phosphorylation to produce metabolic energy. The canonical route of electron transport may diverge by the presence of alternative components to the electron transport chain. The following study comprises the bioinformatic identification and functional characterization of a putative alternative oxidase in the smut fungus f. sp. . This alternative respiratory component has been previously identified in other eukaryotes and is essential for alternative respiration as a response to environmental and chemical stressors, as well as for developmental transitionaoxs during the life cycle of an organism. A growth inhibition assay, using specific mitochondrial inhibitors, functionally confirmed the presence of an antimycin-resistant/salicylhydroxamic acid (SHAM)-sensitive alternative oxidase in the respirasome of . Gene disruption experiments revealed that this enzyme is involved in the pathogenic stage of the fungus, with its absence effectively reducing overall disease incidence in infected maize plants. Furthermore, gene expression analysis revealed that alternative oxidase plays a prominent role in the teliospore developmental stage, in agreement with favoring alternative respiration during quiescent stages of an organism's life cycle.
线粒体电子传递链由经典的蛋白质复合物（I-IV）组成，这些复合物促进电子流动并偶联氧化磷酸化以产生代谢能量。电子传递的经典途径可能会因电子传递链中存在替代成分而发生分歧。以下研究包括对黑粉菌f. sp. 中一种假定的替代氧化酶的生物信息学鉴定和功能表征。这种替代呼吸成分先前已在其他真核生物中被鉴定出来，对于作为对环境和化学应激源的反应的替代呼吸以及生物体生命周期中的发育转变至关重要。使用特定线粒体抑制剂的生长抑制试验在的呼吸体中功能上证实了存在抗霉素抗性/水杨基羟肟酸（SHAM）敏感的替代氧化酶。基因破坏实验表明，这种酶参与了真菌的致病阶段，其缺失有效地降低了感染玉米植株的总体发病率。此外，基因表达分析表明，替代氧化酶在冬孢子发育阶段起着重要作用，这与生物体生命周期静止阶段有利于替代呼吸一致。
