草鱼与团头鲂肠道菌群结构比较分析

COMPARISON OF THE INTESTINAL BACTERIAL COMMUNITIES BETWEEN GRASS CARP(CTENOPHARYNGODON IDELLUS) AND BLUNTNOSE BLACK BREAM(MEGALOBRAMA AMBLYCEPHALA)

选取湖泊养殖的草鱼(Ctenopharyngodon idellus)和团头鲂(Megalobrama amblycephala)为研究对象,通过对其消化道细菌群落16S rDNA进行细菌群落聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)分析,比较了其消化道微生物群落结构。在两种草食性鱼类消化道中分别检测到不同的谱带,其中草鱼的平均谱带数为(33.3±2.8)条,团头鲂的平均谱带数为(38.0±2.5)条。基于所得PCR-DGGE指纹图谱谱带丰度值数据的UPGMA聚类分析和PCA排序均显示草鱼消化道微生物群落并没有与团头鲂消化道微生物群落分开;相比于草鱼和团头鲂消化道微生物群落之间的差异,草鱼和团头鲂个体间差异更加明显,而且草鱼消化道微生物群落的个体分化更为明显。对特定条带的切胶回收测序结果显示,草鱼和团头鲂消化道内检测到的菌群都主要来自γ-变形菌门、梭杆菌门和厚壁菌门,另外草鱼消化道中还检出少量拟杆菌门细菌。以上结果表明同一生境中食性相同的野生草鱼与团头鲂消化道微生物群落组成不存在显著差异,条带回收测序检测到相似的微生物种类。研究结果补充了人们在食性对消化道微生物群落结构影响方面的认识,同时也暗示草鱼和团头鲂消化道内微生物群落对营养物质的代谢方式类似,这为深入研究草食性鱼类消化道微生物菌群参与营养物质代谢积累了资料。

To compare the intestinal bacterial communities of two commercial herbivorous fishes (grass carp and bluntnose black bream), we conducted polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) of 16S rRNA genes. Fishes captured from Wuhu Lake were used to isolate and amplify the variable V3 region of 16S rRNA gene with bacterial domain-specific primers F357 (5￠-CCTACGGGAGGCAGCAG-3￠with GC clamp in the 5￠end) and 518R (5￠-ATTACCGCGGCTGCTGG-3￠). Using both the unweighted pair-group method with arithmetic means (UPGMA) clustering and principal component analysis (PCA) ordination, we observed that the intestinal bacterial communities of the two herbivorous fishes were similar but the individual differences appeared to be more obvious. The results of sequence showed thatγ-Proteobacteria, Fusobacteria, Firmicutes exist both in the intestine of the grass carp and bluntnose black bream; while Bacteroidetes only exist in the bluntnose black bream. A further investigation of feeding habits on bacterial community construction may be of benefit to the aquacultural fundamental research.