Ujszegi János, Boros Zsófia, Harmos Krisztián, Magos Gábor, Tóth Ábris G, Vörös Judit, Kásler Andrea
Department of Evolutionary Ecology, HUN-REN Centre for Agricultural Research, Plant Protection Institute, , Budapest, Hungary.
Department of Systematic Zoology and Ecology, ELTE Eötvös Loránd University, Budapest, Hungary.
Microbiol Spectr. 2025 Sep 2;13(9):e0082625. doi: 10.1128/spectrum.00826-25. Epub 2025 Aug 4.
Survival of amphibian assemblages is threatened by many factors. Among them, chytridiomycosis, the disease caused by the chytrid fungus (Bd), has great importance, also threatening populations of the yellow-bellied toad (), which has a scattered, isolated distribution in Hungary. Treatment with secondary metabolites of the entomopathogenic bacterium is a promising method in the mitigation of chytridiomycosis, as recently demonstrated. To assess whether it may also be effective for lowering infection intensities in tadpoles, we extracted cell-free culture media (CFCM) from liquid cultures of and tested their antifungal efficacy at a dilution of 0.1% (v/v), while also measuring possible short-term malign effects on tadpoles experimentally infected with Bd or sham infection. According to our results, CFCM treatment alone did not compromise tadpoles' survival probability, nor reduce the body mass and developmental rate of the individuals. At the same time, the treatment reduced the intensity and prevalence of Bd infection, but only in the case of one population out of the four tested. The antimicrobial metabolites produced by may therefore be suitable for the safe mitigation of chytridiomycosis in tadpoles, but further studies are needed, aiming to validate and increase the efficacy of this method.IMPORTANCEThe importance of the study is that it offers a potential new microbial tool in the fight against chytridiomycosis, a major threat to amphibian populations worldwide, including the yellow-bellied toad in Hungary. The research tested a promising method using bacterial metabolites of the bacterium to combat the fungal chytrid pathogen. This treatment was safe for tadpoles and capable of reducing infection prevalence. While the results are encouraging, there is a need for further research to improve the treatment's effectiveness. This method could help protect vulnerable species like the yellow-bellied toad from the impacts of chytridiomycosis, which is among the most challenging issues in amphibian conservation.
两栖动物群落的生存受到多种因素的威胁。其中，由壶菌（蛙壶菌，Bd）引起的壶菌病非常重要，它也威胁着黄腹蟾蜍的种群，黄腹蟾蜍在匈牙利分布零散且孤立。正如最近所表明的，用昆虫病原细菌的次生代谢产物进行治疗是缓解壶菌病的一种有前景的方法。为了评估其是否也能有效降低蝌蚪的感染强度，我们从该细菌的液体培养物中提取了无细胞培养基（CFCM），并以0.1%（v/v）的稀释度测试了它们的抗真菌功效，同时还通过实验测量了对感染Bd或假感染的蝌蚪可能产生的短期不良影响。根据我们的结果，单独使用CFCM处理不会影响蝌蚪的存活概率，也不会降低个体的体重和发育速度。同时，该处理降低了Bd感染的强度和患病率，但仅在四个测试种群中的一个种群中出现这种情况。因此，该细菌产生的抗菌代谢产物可能适用于安全缓解蝌蚪的壶菌病，但还需要进一步研究，以验证并提高这种方法的功效。
该研究的重要性在于，它为对抗壶菌病提供了一种潜在的新微生物工具，壶菌病是全球两栖动物种群面临的主要威胁，包括匈牙利的黄腹蟾蜍。该研究测试了一种使用该细菌的细菌代谢产物对抗真菌壶菌病原体的有前景的方法。这种处理对蝌蚪是安全的，并且能够降低感染患病率。虽然结果令人鼓舞，但需要进一步研究以提高该处理的有效性。这种方法可以帮助保护像黄腹蟾蜍这样的脆弱物种免受壶菌病的影响，壶菌病是两栖动物保护中最具挑战性的问题之一。
