Abdallah Ebtsam Sayed Hassan, Mahmoud Mahmoud Mostafa, Abdel-Rahim Ismail Ramadan
Aquatic Animals Medicine and Management, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt.
Botany and Microbiology Department, Faculty of Science, Assiut University, Assiut, Egypt.
J Fish Dis. 2018 Nov;41(11):1719-1732. doi: 10.1111/jfd.12879. Epub 2018 Sep 26.
One hundred and twenty-nine isolates of Trichosporon jirovecii were isolated from the melanized exoskeleton as well as eyestalks, gills, muscle and haemolymph of red swamp crayfish (Procambarus clarkii) collected from the River Nile, during summer 2015. Isolates were similar morphologically, biochemically and genetically. Also, random amplified polymorphic DNA (RAPD) analysis exhibited no polymorphism among the tested isolates. Virulence factors such as chitinase, protease, lipase activities and biofilm formation were examined. Challenge test, using a representative isolate (Tj_ASU8), proved its pathogenicity against crayfish. Magnesium oxide nanoparticles had a good antifungal activity with a minimum fungicidal concentration of 8 mg/ml. To the best of our knowledge, this is the first report for isolation of T. jirovecii from red swamp crayfish, showing melanization, from the River Nile. We assume that infected crayfish may act as a vector for this fungus and can disseminate infection to all susceptible hosts in the vicinity.
2015年夏季，从尼罗河采集的克氏原螯虾（Procambarus clarkii）的黑化外骨骼以及眼柄、鳃、肌肉和血淋巴中分离出129株耶氏毛孢子菌。分离株在形态、生化和遗传方面相似。此外，随机扩增多态性DNA（RAPD）分析显示，受试分离株之间没有多态性。检测了几丁质酶、蛋白酶、脂肪酶活性和生物膜形成等毒力因子。使用代表性分离株（Tj_ASU8）进行的攻毒试验证明了其对小龙虾的致病性。氧化镁纳米颗粒具有良好的抗真菌活性，最低杀菌浓度为8毫克/毫升。据我们所知，这是首次从尼罗河的克氏原螯虾中分离出表现出黑化的耶氏毛孢子菌。我们推测，受感染的小龙虾可能充当这种真菌的载体，并可将感染传播给附近所有易感宿主。
