【摘要】 采用16S rDNA特征序列PCR-DGGE法,分析了不同饵料饲养的暗纹东方鲀的表皮、肠道和河鲀毒素累积组织(肝和卵巢)中可培养细菌的群落组成。根据分子系统发育分析,共鉴定出45种可培养细菌,在这些细菌中,以变形细菌的gamm a亚群占多数,其它分别隶属于低GC含量革兰氏阳性菌和高GC含量革兰氏阳性菌。摄食不同饵料的暗纹东方鲀,其肠道、表皮或河鲀毒素累积组织中的细菌菌落组成是不同的,但不管是摄食人工配合饲料或天然饵料,在暗纹东方鲀的肠道、表皮或河鲀毒素累积组织中,均发现已有报道的可产河鲀毒素的细菌类群,表明饵料来源对暗纹东方鲀的河鲀毒素产生不是必需的。更多还原

【Abstract】 Using 16S rDNA PCR denaturing gradient gel electrophoresis (PCR-DGGE) technology,we investigated the composition of culturable bacterial communities in the skin,intestines,and TTX-accum ulating tissues (ovary,liver) of the obscure striped puffer fish Takifugu obscurus fed natural or artificial diets.Atotal of 45 species of different culturable bacteria were isolated and classified according to phylogenetic analysis.Of these species,those belonging to the class γ-Proteobacteria dominated the microbial community in the puffer fish,while others belonged to the group of low G +C Gram positive bacteria,and the group of high G +C Gram positive bacteria.Large differences in the bacterial assemblage isolated from the intestines,TTX-producing organs and skins of fish fed natural and artificial diets were observed.No matter fed with natural or artificial diets,the tissue of intestine,TTX-accumulating organ,or skin,was found to contain bacteria from TTX-producing genera reported to-date.Puffer fish restricted to artificial diets from birth still had large assemblages of TTX-producing bacteria,indicating thatfood chain accumulation of TTX contributes little to the toxicity of these fish.更多还原