Wan Bowen, Chen Guoling, Poon Emily Shui Kei, Fung Hon Shing, Lau Anthony, Sin Simon Yung Wa
School of Biological Sciences, The University of Hong Kong, Hong Kong, China.
Science Unit, Lingnan University, Hong Kong, China.
Integr Zool. 2025 Mar;20(2):236-255. doi: 10.1111/1749-4877.12855. Epub 2024 Jun 13.
Chytridiomycosis, an infectious skin disease caused by the chytrid fungi, Batrachochytrium dendrobatidis and B. salamandrivorans, poses a significant threat to amphibian biodiversity worldwide. Antifungal bacteria found on the skin of chytrid-resistant amphibians could potentially provide defense against chytridiomycosis and lower mortality rates among resistant individuals. The Hong Kong newt (Paramesotriton hongkongensis) is native to East Asia, a region suspected to be the origin of chytrids, and has exhibited asymptomatic infection, suggesting a long-term coexistence with the chytrids. Therefore, the skin microbiota of this resistant species warrant investigation, along with other factors that can affect the microbiota. Among the 149 newts sampled in their natural habitats in Hong Kong, China, putative antifungal bacteria were found in all individuals. There were 314 amplicon sequence variants distributed over 25 genera of putative antifungal bacteria; abundant ones included Acinetobacter, Flavobacterium, and Novosphingobium spp. The skin microbiota compositions were strongly influenced by the inter-site geographical distances. Despite inter-site differences, we identified some core skin microbes across sites that could be vital to P. hongkongensis. The dominant cores included the family Comamonadaceae, family Chitinophagaceae, and class Betaproteobacteria. Moreover, habitat elevation and host sex also exhibited significant effects on skin microbiota compositions. The antifungal bacteria found on these newts offer an important resource for conservation against chytridiomycosis, such as developing probiotic treatments for susceptible species.
壶菌病是一种由壶菌真菌——蛙壶菌和蝾螈壶菌引起的传染性皮肤病,对全球两栖动物生物多样性构成重大威胁。在对壶菌具有抗性的两栖动物皮肤上发现的抗真菌细菌可能为抵御壶菌病提供防御,并降低抗性个体的死亡率。香港瘰螈原产于东亚,该地区被怀疑是壶菌的起源地,并且已表现出无症状感染,这表明其与壶菌长期共存。因此,这种抗性物种的皮肤微生物群以及其他可能影响微生物群的因素值得研究。在中国香港的自然栖息地采集的149只瘰螈中,所有个体都发现了推定的抗真菌细菌。有314个扩增子序列变体分布在25个推定的抗真菌细菌属中;丰富的属包括不动杆菌属、黄杆菌属和新鞘氨醇菌属。皮肤微生物群的组成受到不同地点间地理距离的强烈影响。尽管不同地点存在差异,但我们确定了一些跨地点的核心皮肤微生物,它们可能对香港瘰螈至关重要。主要的核心包括丛毛单胞菌科、噬几丁质菌科和β-变形菌纲。此外,栖息地海拔和宿主性别对皮肤微生物群组成也有显著影响。在这些瘰螈身上发现的抗真菌细菌为防治壶菌病提供了重要资源,例如为易感物种开发益生菌疗法。