Chahed Abdessalem, Nesler Andrea, Navazio Lorella, Baldan Barbara, Busato Isabella, Ait Barka Essaid, Pertot Ilaria, Puopolo Gerardo, Perazzolli Michele
Department of Sustainable Agro-Ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Italy.
Biological Products for Agriculture (Bi-PA), Londerzeel, Belgium.
Front Microbiol. 2020 Feb 6;11:128. doi: 10.3389/fmicb.2020.00128. eCollection 2020.
Rare sugars are monosaccharides with limited availability in nature and their biological functions are largely unknown. Among them, tagatose was developed as a low-calorie sweetener and showed beneficial effects on human health. Tagatose is metabolized by only certain microbial taxa and inhibits the growth of important crop pathogens (e.g., ), but its mode of action and the microbial responses are unknown. The aim of this study was to understand the tagatose mode of action against spp., with the final aim of developing new plant protection products. Tagatose inhibited growth and caused severe ultrastructural alterations, with the formation of circular and concentric mitochondrial cristae. Decreased ATP content and reduced oxygen consumption rate (OCR) were found in tagatose-incubated as compared to the control, with the consequent accumulation of reactive oxygen species (ROS) and induction of genes related to apoptosis and oxidative stress response. On the other hand, tagatose did not, or only slightly, affect the growth, cellular ultrastructure and mitochondrial processes in , indicating a species-specific response to this rare sugar. The mode of action of tagatose against was mainly based on the inhibition of mitochondrial processes and this rare sugar seems to be a promising active substance for the further development of eco-friendly fungicides, thanks to its anti-nutritional properties on some phytopathogens and low risk for human health.
稀有糖是自然界中可用性有限的单糖，其生物学功能大多未知。其中，塔格糖被开发为一种低热量甜味剂，并对人体健康显示出有益作用。塔格糖仅被某些微生物类群代谢，并抑制重要作物病原体（如 ）的生长，但其作用方式和微生物反应尚不清楚。本研究的目的是了解塔格糖对 spp. 的作用方式，最终目标是开发新的植物保护产品。塔格糖抑制 生长并引起严重的超微结构改变，形成圆形和同心的线粒体嵴。与对照相比，在经塔格糖处理的 中发现ATP含量降低和氧消耗率（OCR）降低，从而导致活性氧（ROS）积累以及与细胞凋亡和氧化应激反应相关的基因被诱导。另一方面，塔格糖对 的生长、细胞超微结构和线粒体过程没有影响或仅有轻微影响，表明对这种稀有糖存在物种特异性反应。塔格糖对 的作用方式主要基于对线粒体过程的抑制，由于其对某些植物病原体具有抗营养特性且对人类健康风险较低，这种稀有糖似乎是进一步开发环保型杀菌剂的有前景的活性物质。
