Siriyappagouder Prabhugouda, Kiron Viswanath, Lokesh Jep, Rajeish Moger, Kopp Martina, Fernandes Jorge
Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway.
College of Fisheries, Karnataka Veterinary, Animal and Fisheries Sciences University, Mangalore, India.
Front Microbiol. 2018 Mar 6;9:387. doi: 10.3389/fmicb.2018.00387. eCollection 2018.
As an integral part of the resident microbial community of fish intestinal tract, the mycobiota is expected to play important roles in health and disease resistance of the host. The composition of the diverse fungal communities, which colonize the intestine, is greatly influenced by the host, their diet and geographic origin. Studies of fungal communities are rare and the majority of previous studies have relied on culture-based methods. In particular, fungal communities in fish are also poorly characterized. The aim of this study was to provide an in-depth overview of the intestinal mycobiota in a model fish species (zebrafish, ) and to determine differences in fungal composition between wild and captive specimens. We have profiled the intestinal mycobiota of wild-caught (Sharavati River, India), laboratory-reared (Bodø, Norway) and wild-caught-laboratory-kept (Uttara, India) zebrafish by sequencing the fungal internal transcribed spacer 2 region on the Illumina MiSeq platform. Wild fish were exposed to variable environmental factors, whereas both laboratory groups were kept in controlled conditions. There were also differences in husbandry practices at Bodø and Uttara, particularly diet. Zebrafish from Bodø were reared in the laboratory for over 10 generations, while wild-caught-laboratory-kept fish from Uttara were housed in the laboratory for only 2 months before sample collection. The intestine of zebrafish contained members of more than 15 fungal classes belonging to the phyla Ascomycota, Basidiomycota, and Zygomycota. Fungal species richness and diversity distinguished the wild-caught and laboratory-reared zebrafish communities. Wild-caught zebrafish-associated mycobiota comprised mainly Dothideomycetes in contrast to their Saccharomycetes-dominated laboratory-reared counterparts. The predominant Saccharomycetes in laboratory-reared fish belonged to the saprotrophic guild. Another characteristic feature of laboratory-reared fish was the significantly higher abundance of (Tremellomycetes) compared to wild fish. This pioneer study has shed light into the differences in the intestinal fungal communities of wild-caught and laboratory-reared zebrafish and the baseline data generated will enrich our knowledge on fish mycobiota.
作为鱼类肠道常驻微生物群落的一个组成部分，真菌微生物群有望在宿主的健康和抗病性方面发挥重要作用。定殖于肠道的多样真菌群落的组成，受到宿主、其饮食和地理来源的极大影响。对真菌群落的研究很少见，而且大多数先前的研究都依赖基于培养的方法。特别是，鱼类中的真菌群落也缺乏充分的特征描述。本研究的目的是深入概述一种模式鱼类（斑马鱼）的肠道真菌微生物群，并确定野生和圈养标本之间真菌组成的差异。我们通过在Illumina MiSeq平台上对真菌内部转录间隔区2区域进行测序，分析了野生捕获（印度沙拉瓦蒂河）、实验室饲养（挪威博德）和野生捕获后在实验室饲养（印度乌塔拉）的斑马鱼的肠道真菌微生物群。野生鱼暴露于可变的环境因素，而两个实验室组都饲养在可控条件下。博德和乌塔拉的饲养方式也存在差异，特别是饮食方面。来自博德的斑马鱼在实验室饲养了10代以上，而来自乌塔拉的野生捕获后在实验室饲养的鱼在采样前仅在实验室饲养了2个月。斑马鱼的肠道包含属于子囊菌门、担子菌门和接合菌门的15个以上真菌类别的成员。真菌物种丰富度和多样性区分了野生捕获和实验室饲养的斑马鱼群落。与以酵母菌为主的实验室饲养的斑马鱼相比，野生捕获的斑马鱼相关真菌微生物群主要由座囊菌纲组成。实验室饲养的鱼类中占主导地位的酵母菌属于腐生菌 guild。实验室饲养的鱼类的另一个特征是与野生鱼相比，银耳纲（银耳菌纲）的丰度显著更高。这项开创性研究揭示了野生捕获和实验室饲养的斑马鱼肠道真菌群落的差异，所产生的基线数据将丰富我们对鱼类真菌微生物群的认识。
