Hutchings Michelle L, Alpha-Cobb Cambria J, Hiller David A, Berro Julien, Strobel Scott A
From the Departments of Chemistry and.
Molecular Biophysics and Biochemistry, Chemical Biology Institute, and.
J Biol Chem. 2017 May 5;292(18):7358-7371. doi: 10.1074/jbc.M117.779009. Epub 2017 Mar 10.
Antagonistic microorganisms produce antimicrobials to inhibit the growth of competitors. Although water-soluble antimicrobials are limited to proximal interactions via aqueous diffusion, volatile antimicrobials are able to act at a distance and diffuse through heterogeneous environments. Here, we identify the mechanism of action of , an endophytic fungus known for its volatile antimicrobial activity toward a wide range of human and plant pathogens and its potential use in mycofumigation. Proposed uses of the species include protecting crops, produce, and building materials from undesired fungal or bacterial growth. By analyzing a collection of isolates with varying toxicity, we demonstrate that the volatile mycotoxin, -methyl--nitrosoisobutyramide, is the dominant factor in toxicity and acts primarily through DNA methylation. Additionally, isolates exhibit higher resistance to DNA methylation compared with other fungi. This work contributes to the evaluation of isolates as potential mycofumigants, provides insight into chemical strategies that organisms use to manipulate their environment, and provokes questions regarding the mechanisms of resistance used to tolerate constitutive, long-term exposure to DNA methylation.
拮抗微生物产生抗菌物质以抑制竞争者的生长。虽然水溶性抗菌物质通过水扩散仅限于近端相互作用，但挥发性抗菌物质能够在一定距离起作用并扩散通过异质环境。在此，我们确定了一种内生真菌的作用机制，该真菌以其对多种人类和植物病原体的挥发性抗菌活性及其在熏蒸防霉中的潜在用途而闻名。该真菌物种的拟用用途包括保护作物、农产品和建筑材料免受不期望的真菌或细菌生长的影响。通过分析一系列具有不同毒性的分离株，我们证明挥发性霉菌毒素——N-甲基-N-亚硝基异丁酰胺是该真菌毒性的主要因素，并且主要通过DNA甲基化起作用。此外，与其他真菌相比，该真菌分离株对DNA甲基化表现出更高的抗性。这项工作有助于评估该真菌分离株作为潜在熏蒸防霉剂的可能性，深入了解生物体用于操纵其环境的化学策略，并引发了关于用于耐受组成性、长期DNA甲基化暴露的抗性机制的问题。
